diff --git a/lib/api/model/events.dart b/lib/api/model/events.dart
index c03e29fae2..205b1c8077 100644
--- a/lib/api/model/events.dart
+++ b/lib/api/model/events.dart
@@ -29,6 +29,13 @@ sealed class Event {
           case 'update': return UserSettingsUpdateEvent.fromJson(json);
           default: return UnexpectedEvent.fromJson(json);
         }
+      case 'device':
+        switch (json['op'] as String) {
+          case 'add': return DeviceAddEvent.fromJson(json);
+          case 'remove': return DeviceRemoveEvent.fromJson(json);
+          case 'update': return DeviceUpdateEvent.fromJson(json);
+          default: return UnexpectedEvent.fromJson(json);
+        }
       case 'custom_profile_fields': return CustomProfileFieldsEvent.fromJson(json);
       case 'user_group':
         switch (json['op'] as String) {
@@ -210,6 +217,95 @@ class UserSettingsUpdateEvent extends Event {
   Map<String, dynamic> toJson() => _$UserSettingsUpdateEventToJson(this);
 }
 
+/// A Zulip event of type `device`.
+///
+/// See API docs starting at:
+///   https://zulip.com/api/get-events#device-add
+sealed class DeviceEvent extends Event {
+  @override
+  @JsonKey(includeToJson: true)
+  String get type => 'device';
+
+  String get op;
+
+  final int deviceId;
+
+  DeviceEvent({required super.id, required this.deviceId});
+}
+
+/// A [DeviceEvent] with op `add`: https://zulip.com/api/get-events#device-add
+@JsonSerializable(fieldRename: FieldRename.snake)
+class DeviceAddEvent extends DeviceEvent {
+  @override
+  @JsonKey(includeToJson: true)
+  String get op => 'add';
+
+  DeviceAddEvent({required super.id, required super.deviceId});
+
+  factory DeviceAddEvent.fromJson(Map<String, dynamic> json) =>
+    _$DeviceAddEventFromJson(json);
+
+  @override
+  Map<String, dynamic> toJson() => _$DeviceAddEventToJson(this);
+}
+
+/// A [DeviceEvent] with op `remove`: https://zulip.com/api/get-events#device-remove
+@JsonSerializable(fieldRename: FieldRename.snake)
+class DeviceRemoveEvent extends DeviceEvent {
+  @override
+  @JsonKey(includeToJson: true)
+  String get op => 'remove';
+
+  DeviceRemoveEvent({required super.id, required super.deviceId});
+
+  factory DeviceRemoveEvent.fromJson(Map<String, dynamic> json) =>
+    _$DeviceRemoveEventFromJson(json);
+
+  @override
+  Map<String, dynamic> toJson() => _$DeviceRemoveEventToJson(this);
+}
+
+/// A [DeviceEvent] with op `update`: https://zulip.com/api/get-events#device-update
+@JsonSerializable(fieldRename: FieldRename.snake)
+@NullableIntJsonConverter()
+@NullableStringJsonConverter()
+class DeviceUpdateEvent extends DeviceEvent {
+  @override
+  @JsonKey(includeToJson: true)
+  String get op => 'update';
+
+  @JsonKey(readValue: JsonNullable.readIntFromJson)
+  final JsonNullable<int>? pushKeyId;
+
+  @JsonKey(readValue: JsonNullable.readStringFromJson)
+  final JsonNullable<String>? pushTokenId;
+
+  @JsonKey(readValue: JsonNullable.readStringFromJson)
+  final JsonNullable<String>? pendingPushTokenId;
+
+  @JsonKey(readValue: JsonNullable.readIntFromJson)
+  final JsonNullable<int>? pushTokenLastUpdatedTimestamp;
+
+  @JsonKey(readValue: JsonNullable.readStringFromJson)
+  final JsonNullable<String>? pushRegistrationErrorCode;
+
+  DeviceUpdateEvent({
+    required super.id,
+    required super.deviceId,
+    required this.pushKeyId,
+    required this.pushTokenId,
+    required this.pendingPushTokenId,
+    required this.pushTokenLastUpdatedTimestamp,
+    required this.pushRegistrationErrorCode,
+  });
+
+  factory DeviceUpdateEvent.fromJson(Map<String, dynamic> json) =>
+    _$DeviceUpdateEventFromJson(json);
+
+  @override
+  Map<String, dynamic> toJson() => _$DeviceUpdateEventToJson(this);
+}
+
 /// A Zulip event of type `custom_profile_fields`: https://zulip.com/api/get-events#custom_profile_fields
 @JsonSerializable(fieldRename: FieldRename.snake)
 class CustomProfileFieldsEvent extends Event {
diff --git a/lib/api/model/events.g.dart b/lib/api/model/events.g.dart
index 63e5fb347a..a89c7ddd8f 100644
--- a/lib/api/model/events.g.dart
+++ b/lib/api/model/events.g.dart
@@ -71,6 +71,108 @@ const _$UserSettingNameEnumMap = {
   UserSettingName.presenceEnabled: 'presence_enabled',
 };
 
+DeviceAddEvent _$DeviceAddEventFromJson(Map<String, dynamic> json) =>
+    DeviceAddEvent(
+      id: (json['id'] as num).toInt(),
+      deviceId: (json['device_id'] as num).toInt(),
+    );
+
+Map<String, dynamic> _$DeviceAddEventToJson(DeviceAddEvent instance) =>
+    <String, dynamic>{
+      'id': instance.id,
+      'type': instance.type,
+      'device_id': instance.deviceId,
+      'op': instance.op,
+    };
+
+DeviceRemoveEvent _$DeviceRemoveEventFromJson(Map<String, dynamic> json) =>
+    DeviceRemoveEvent(
+      id: (json['id'] as num).toInt(),
+      deviceId: (json['device_id'] as num).toInt(),
+    );
+
+Map<String, dynamic> _$DeviceRemoveEventToJson(DeviceRemoveEvent instance) =>
+    <String, dynamic>{
+      'id': instance.id,
+      'type': instance.type,
+      'device_id': instance.deviceId,
+      'op': instance.op,
+    };
+
+DeviceUpdateEvent _$DeviceUpdateEventFromJson(
+  Map<String, dynamic> json,
+) => DeviceUpdateEvent(
+  id: (json['id'] as num).toInt(),
+  deviceId: (json['device_id'] as num).toInt(),
+  pushKeyId: _$JsonConverterFromJson<JsonNullable<int>, JsonNullable<int>>(
+    JsonNullable.readIntFromJson(json, 'push_key_id'),
+    const NullableIntJsonConverter().fromJson,
+  ),
+  pushTokenId:
+      _$JsonConverterFromJson<JsonNullable<String>, JsonNullable<String>>(
+        JsonNullable.readStringFromJson(json, 'push_token_id'),
+        const NullableStringJsonConverter().fromJson,
+      ),
+  pendingPushTokenId:
+      _$JsonConverterFromJson<JsonNullable<String>, JsonNullable<String>>(
+        JsonNullable.readStringFromJson(json, 'pending_push_token_id'),
+        const NullableStringJsonConverter().fromJson,
+      ),
+  pushTokenLastUpdatedTimestamp:
+      _$JsonConverterFromJson<JsonNullable<int>, JsonNullable<int>>(
+        JsonNullable.readIntFromJson(json, 'push_token_last_updated_timestamp'),
+        const NullableIntJsonConverter().fromJson,
+      ),
+  pushRegistrationErrorCode:
+      _$JsonConverterFromJson<JsonNullable<String>, JsonNullable<String>>(
+        JsonNullable.readStringFromJson(json, 'push_registration_error_code'),
+        const NullableStringJsonConverter().fromJson,
+      ),
+);
+
+Map<String, dynamic> _$DeviceUpdateEventToJson(
+  DeviceUpdateEvent instance,
+) => <String, dynamic>{
+  'id': instance.id,
+  'type': instance.type,
+  'device_id': instance.deviceId,
+  'op': instance.op,
+  'push_key_id': _$JsonConverterToJson<JsonNullable<int>, JsonNullable<int>>(
+    instance.pushKeyId,
+    const NullableIntJsonConverter().toJson,
+  ),
+  'push_token_id':
+      _$JsonConverterToJson<JsonNullable<String>, JsonNullable<String>>(
+        instance.pushTokenId,
+        const NullableStringJsonConverter().toJson,
+      ),
+  'pending_push_token_id':
+      _$JsonConverterToJson<JsonNullable<String>, JsonNullable<String>>(
+        instance.pendingPushTokenId,
+        const NullableStringJsonConverter().toJson,
+      ),
+  'push_token_last_updated_timestamp':
+      _$JsonConverterToJson<JsonNullable<int>, JsonNullable<int>>(
+        instance.pushTokenLastUpdatedTimestamp,
+        const NullableIntJsonConverter().toJson,
+      ),
+  'push_registration_error_code':
+      _$JsonConverterToJson<JsonNullable<String>, JsonNullable<String>>(
+        instance.pushRegistrationErrorCode,
+        const NullableStringJsonConverter().toJson,
+      ),
+};
+
+Value? _$JsonConverterFromJson<Json, Value>(
+  Object? json,
+  Value? Function(Json json) fromJson,
+) => json == null ? null : fromJson(json as Json);
+
+Json? _$JsonConverterToJson<Json, Value>(
+  Value? value,
+  Json? Function(Value value) toJson,
+) => value == null ? null : toJson(value);
+
 CustomProfileFieldsEvent _$CustomProfileFieldsEventFromJson(
   Map<String, dynamic> json,
 ) => CustomProfileFieldsEvent(
@@ -333,16 +435,6 @@ const _$UserRoleEnumMap = {
   UserRole.unknown: null,
 };
 
-Value? _$JsonConverterFromJson<Json, Value>(
-  Object? json,
-  Value? Function(Json json) fromJson,
-) => json == null ? null : fromJson(json as Json);
-
-Json? _$JsonConverterToJson<Json, Value>(
-  Value? value,
-  Json? Function(Value value) toJson,
-) => value == null ? null : toJson(value);
-
 SavedSnippetsAddEvent _$SavedSnippetsAddEventFromJson(
   Map<String, dynamic> json,
 ) => SavedSnippetsAddEvent(
diff --git a/lib/api/model/initial_snapshot.dart b/lib/api/model/initial_snapshot.dart
index 203adf5a41..9c1dab4180 100644
--- a/lib/api/model/initial_snapshot.dart
+++ b/lib/api/model/initial_snapshot.dart
@@ -78,6 +78,8 @@ class InitialSnapshot {
 
   final List<UserTopicItem> userTopics;
 
+  final Map<int, ClientDevice>? devices; // TODO(server-12)
+
   final GroupSettingValue? realmCanDeleteAnyMessageGroup; // TODO(server-10)
 
   final GroupSettingValue? realmCanDeleteOwnMessageGroup; // TODO(server-10)
@@ -188,6 +190,7 @@ class InitialSnapshot {
     required this.userStatuses,
     required this.userSettings,
     required this.userTopics,
+    required this.devices,
     required this.realmCanDeleteAnyMessageGroup,
     required this.realmCanDeleteOwnMessageGroup,
     required this.realmDeleteOwnMessagePolicy,
diff --git a/lib/api/model/initial_snapshot.g.dart b/lib/api/model/initial_snapshot.g.dart
index 094b923623..dd535eee21 100644
--- a/lib/api/model/initial_snapshot.g.dart
+++ b/lib/api/model/initial_snapshot.g.dart
@@ -89,6 +89,12 @@ InitialSnapshot _$InitialSnapshotFromJson(
   userTopics: (json['user_topics'] as List<dynamic>)
       .map((e) => UserTopicItem.fromJson(e as Map<String, dynamic>))
       .toList(),
+  devices: (json['devices'] as Map<String, dynamic>?)?.map(
+    (k, e) => MapEntry(
+      int.parse(k),
+      ClientDevice.fromJson(e as Map<String, dynamic>),
+    ),
+  ),
   realmCanDeleteAnyMessageGroup:
       json['realm_can_delete_any_message_group'] == null
       ? null
@@ -188,6 +194,7 @@ Map<String, dynamic> _$InitialSnapshotToJson(
   'user_status': instance.userStatuses.map((k, e) => MapEntry(k.toString(), e)),
   'user_settings': instance.userSettings,
   'user_topics': instance.userTopics,
+  'devices': instance.devices?.map((k, e) => MapEntry(k.toString(), e)),
   'realm_can_delete_any_message_group': instance.realmCanDeleteAnyMessageGroup,
   'realm_can_delete_own_message_group': instance.realmCanDeleteOwnMessageGroup,
   'realm_delete_own_message_policy': instance.realmDeleteOwnMessagePolicy,
diff --git a/lib/api/model/json.dart b/lib/api/model/json.dart
index 092b047f83..10e25fcefb 100644
--- a/lib/api/model/json.dart
+++ b/lib/api/model/json.dart
@@ -12,16 +12,54 @@ import 'package:json_annotation/json_annotation.dart';
 /// the `name` property being absent in JSON;
 /// a value of `JsonNullable(null)` represents `'name': null` in JSON;
 /// and a value of `JsonNullable("foo")` represents `'name': 'foo'` in JSON.
+///
+/// To use this class with [JsonSerializable]:
+///  * On the field, apply [JsonKey.readValue] with a method from the
+///    [readFromJson] family.
+///  * On either the field or the class, apply an [IdentityJsonConverter]
+///    subclass such as [NullableIntJsonConverter].
+///  * Both the read method and the converter need to have a concrete type,
+///    not generic in T, because of limitations in `package:json_serializable`.
+///    Go ahead and add them for more concrete types whenever needed.
 class JsonNullable<T extends Object> {
   const JsonNullable(this.value);
 
   final T? value;
 
+  /// Reads a [JsonNullable] from a JSON map, as in [JsonKey.readValue].
+  ///
+  /// The method actually passed to [JsonKey.readValue] needs a concrete type;
+  /// see the wrapper methods [readIntFromJson] and [readStringFromJson],
+  /// and add more freely as needed.
+  ///
+  /// This generic version is useful when writing a custom [JsonKey.readValue]
+  /// callback for other reasons, as well as for implementing those wrappers.
+  ///
+  /// Because the [JsonKey.readValue] return value is expected to still be
+  /// a JSON-like value that needs conversion,
+  /// the field (or the class) will also need to be annotated with
+  /// [IdentityJsonConverter] or a subclass.
+  /// The converter tells `package:json_serializable` how to convert
+  /// the [JsonNullable] from JSON: namely, by doing nothing.
   static JsonNullable<T>? readFromJson<T extends Object>(
       Map<dynamic, dynamic> map, String key) {
     return map.containsKey(key) ? JsonNullable(map[key] as T?) : null;
   }
 
+  /// Reads a [JsonNullable<int>] from a JSON map, as in [JsonKey.readValue].
+  ///
+  /// The field or class will need to be annotated with [NullableIntJsonConverter].
+  /// See [readFromJson].
+  static JsonNullable<int>? readIntFromJson(Map<dynamic, dynamic> map, String key) =>
+    readFromJson<int>(map, key);
+
+  /// Reads a [JsonNullable<String>] from a JSON map, as in [JsonKey.readValue].
+  ///
+  /// The field or class will need to be annotated with [NullableStringJsonConverter].
+  /// See [readFromJson].
+  static JsonNullable<String>? readStringFromJson(Map<dynamic, dynamic> map, String key) =>
+    readFromJson<String>(map, key);
+
   @override
   bool operator ==(Object other) {
     if (other is! JsonNullable) return false;
@@ -32,6 +70,19 @@ class JsonNullable<T extends Object> {
   int get hashCode => Object.hash('JsonNullable', value);
 }
 
+/// "Converts" a value to and from JSON by using the value unmodified.
+///
+/// This is useful when e.g. a [JsonKey.readValue] callback has already
+/// effectively converted the value from JSON,
+/// as [JsonNullable.readFromJson] does.
+///
+/// The converter actually applied as an annotation needs a specific type.
+/// Just writing `@IdentityJsonConverter<…>` directly as the annotation
+/// doesn't work, as `package:json_serializable` gets confused;
+/// instead, use a subclass like [NullableIntJsonConverter],
+/// and add new such subclasses whenever needed.
+// Possibly related to that issue with a generic converter:
+//   https://github.com/google/json_serializable.dart/issues/1398
 class IdentityJsonConverter<T> extends JsonConverter<T, T> {
   const IdentityJsonConverter();
 
@@ -42,10 +93,18 @@ class IdentityJsonConverter<T> extends JsonConverter<T, T> {
   T toJson(T object) => object;
 }
 
-// Make similar IdentityJsonConverter<…> subclasses as needed.
-// Just writing `@IdentityJsonConverter<…>` directly as the annotation
-// doesn't work, as json_serializable gets confused.  Possibly related:
-//   https://github.com/google/json_serializable.dart/issues/1398
+/// "Converts" a [JsonNullable<int>] to and from JSON by using it unmodified.
+///
+/// This is useful with [JsonNullable.readIntFromJson].
+/// See there, and the base class [IdentityJsonConverter].
+class NullableIntJsonConverter extends IdentityJsonConverter<JsonNullable<int>> {
+  const NullableIntJsonConverter();
+}
+
+/// "Converts" a [JsonNullable<String>] to and from JSON by using it unmodified.
+///
+/// This is useful with [JsonNullable.readStringFromJson].
+/// See there, and the base class [IdentityJsonConverter].
 class NullableStringJsonConverter extends IdentityJsonConverter<JsonNullable<String>> {
   const NullableStringJsonConverter();
 }
diff --git a/lib/api/model/model.dart b/lib/api/model/model.dart
index 794103dd8a..9e5d8227d2 100644
--- a/lib/api/model/model.dart
+++ b/lib/api/model/model.dart
@@ -407,6 +407,28 @@ enum Emojiset {
   String toJson() => _$EmojisetEnumMap[this]!;
 }
 
+@JsonSerializable(fieldRename: FieldRename.snake)
+class ClientDevice {
+  int? pushKeyId;
+  String? pushTokenId;
+  String? pendingPushTokenId;
+  int? pushTokenLastUpdatedTimestamp;
+  String? pushRegistrationErrorCode;
+
+  ClientDevice({
+    required this.pushKeyId,
+    required this.pushTokenId,
+    required this.pendingPushTokenId,
+    required this.pushTokenLastUpdatedTimestamp,
+    required this.pushRegistrationErrorCode,
+  });
+
+  factory ClientDevice.fromJson(Map<String, dynamic> json) =>
+    _$ClientDeviceFromJson(json);
+
+  Map<String, dynamic> toJson() => _$ClientDeviceToJson(this);
+}
+
 /// As in [InitialSnapshot.realmUserGroups] or [UserGroupAddEvent].
 @JsonSerializable(fieldRename: FieldRename.snake)
 class UserGroup {
diff --git a/lib/api/model/model.g.dart b/lib/api/model/model.g.dart
index 489e3900ed..0c7d2dcd0e 100644
--- a/lib/api/model/model.g.dart
+++ b/lib/api/model/model.g.dart
@@ -112,6 +112,25 @@ Map<String, dynamic> _$RealmEmojiItemToJson(RealmEmojiItem instance) =>
       'author_id': instance.authorId,
     };
 
+ClientDevice _$ClientDeviceFromJson(Map<String, dynamic> json) => ClientDevice(
+  pushKeyId: (json['push_key_id'] as num?)?.toInt(),
+  pushTokenId: json['push_token_id'] as String?,
+  pendingPushTokenId: json['pending_push_token_id'] as String?,
+  pushTokenLastUpdatedTimestamp:
+      (json['push_token_last_updated_timestamp'] as num?)?.toInt(),
+  pushRegistrationErrorCode: json['push_registration_error_code'] as String?,
+);
+
+Map<String, dynamic> _$ClientDeviceToJson(
+  ClientDevice instance,
+) => <String, dynamic>{
+  'push_key_id': instance.pushKeyId,
+  'push_token_id': instance.pushTokenId,
+  'pending_push_token_id': instance.pendingPushTokenId,
+  'push_token_last_updated_timestamp': instance.pushTokenLastUpdatedTimestamp,
+  'push_registration_error_code': instance.pushRegistrationErrorCode,
+};
+
 UserGroup _$UserGroupFromJson(Map<String, dynamic> json) => UserGroup(
   id: (json['id'] as num).toInt(),
   members: (json['members'] as List<dynamic>)
diff --git a/lib/api/notifications.dart b/lib/api/notifications.dart
index 1dae8bbe93..beb6d42e55 100644
--- a/lib/api/notifications.dart
+++ b/lib/api/notifications.dart
@@ -1,11 +1,40 @@
 
+import 'dart:convert';
+import 'dart:typed_data';
+
 import 'package:json_annotation/json_annotation.dart';
 
 import 'model/model.dart';
 
 part 'notifications.g.dart';
 
-/// Parsed version of an FCM message, of any type.
+/// An FCM message whose contents are encrypted end-to-end from the Zulip server.
+///
+/// Once decrypted, the contents will become an [FcmMessage].
+/// See there also for background on FCM and FCM messages.
+///
+/// API docs:
+///   https://zulip.com/api/mobile-notifications#data-sent-to-fcm
+@JsonSerializable(fieldRename: FieldRename.snake)
+class EncryptedFcmMessage {
+  @_IntConverter()
+  final int pushKeyId;
+
+  @JsonKey(fromJson: base64Decode, toJson: base64Encode)
+  final Uint8List encryptedData;
+
+  EncryptedFcmMessage({required this.pushKeyId, required this.encryptedData});
+
+  factory EncryptedFcmMessage.fromJson(Map<String, dynamic> json) =>
+    _$EncryptedFcmMessageFromJson(json);
+
+  Map<String, dynamic> toJson() => _$EncryptedFcmMessageToJson(this);
+}
+
+/// Parsed version of an FCM message, of any plaintext type.
+///
+/// This represents the data either decrypted from an [EncryptedFcmMessage],
+/// or (TODO(server-12)) delivered in plaintext directly as an FCM payload.
 ///
 /// For partial API docs, see:
 ///   https://zulip.com/api/mobile-notifications
diff --git a/lib/api/notifications.g.dart b/lib/api/notifications.g.dart
index 43e08dc4e8..2e50cfc571 100644
--- a/lib/api/notifications.g.dart
+++ b/lib/api/notifications.g.dart
@@ -8,6 +8,19 @@ part of 'notifications.dart';
 // JsonSerializableGenerator
 // **************************************************************************
 
+EncryptedFcmMessage _$EncryptedFcmMessageFromJson(Map<String, dynamic> json) =>
+    EncryptedFcmMessage(
+      pushKeyId: const _IntConverter().fromJson(json['push_key_id'] as String),
+      encryptedData: base64Decode(json['encrypted_data'] as String),
+    );
+
+Map<String, dynamic> _$EncryptedFcmMessageToJson(
+  EncryptedFcmMessage instance,
+) => <String, dynamic>{
+  'push_key_id': const _IntConverter().toJson(instance.pushKeyId),
+  'encrypted_data': base64Encode(instance.encryptedData),
+};
+
 MessageFcmMessage _$MessageFcmMessageFromJson(Map<String, dynamic> json) =>
     MessageFcmMessage(
       realmUrl: Uri.parse(
diff --git a/lib/api/route/account.dart b/lib/api/route/account.dart
index 1d29d3da1c..ba6bd23f44 100644
--- a/lib/api/route/account.dart
+++ b/lib/api/route/account.dart
@@ -32,3 +32,22 @@ class FetchApiKeyResult {
 
   Map<String, dynamic> toJson() => _$FetchApiKeyResultToJson(this);
 }
+
+/// https://zulip.com/api/register-client-device
+Future<RegisterClientDeviceResult> registerClientDevice(ApiConnection connection) {
+  return connection.post('registerClientDevice', RegisterClientDeviceResult.fromJson, 'register_client_device', {});
+}
+
+@JsonSerializable(fieldRename: FieldRename.snake)
+class RegisterClientDeviceResult {
+  final int deviceId;
+
+  RegisterClientDeviceResult({
+    required this.deviceId,
+  });
+
+  factory RegisterClientDeviceResult.fromJson(Map<String, dynamic> json) =>
+    _$RegisterClientDeviceResultFromJson(json);
+
+  Map<String, dynamic> toJson() => _$RegisterClientDeviceResultToJson(this);
+}
diff --git a/lib/api/route/account.g.dart b/lib/api/route/account.g.dart
index b46fd098b9..031792b75f 100644
--- a/lib/api/route/account.g.dart
+++ b/lib/api/route/account.g.dart
@@ -21,3 +21,11 @@ Map<String, dynamic> _$FetchApiKeyResultToJson(FetchApiKeyResult instance) =>
       'email': instance.email,
       'user_id': instance.userId,
     };
+
+RegisterClientDeviceResult _$RegisterClientDeviceResultFromJson(
+  Map<String, dynamic> json,
+) => RegisterClientDeviceResult(deviceId: (json['device_id'] as num).toInt());
+
+Map<String, dynamic> _$RegisterClientDeviceResultToJson(
+  RegisterClientDeviceResult instance,
+) => <String, dynamic>{'device_id': instance.deviceId};
diff --git a/lib/api/route/notifications.dart b/lib/api/route/notifications.dart
index a8c7b23b36..5336f93e9f 100644
--- a/lib/api/route/notifications.dart
+++ b/lib/api/route/notifications.dart
@@ -1,5 +1,88 @@
+import 'package:json_annotation/json_annotation.dart';
+
 import '../core.dart';
 
+part 'notifications.g.dart';
+
+/// https://zulip.com/api/register-push-device
+///
+/// The request's parameters are grouped here into [key] and [token]
+/// to reflect the API's structure where each of those groups must be
+/// either entirely absent or entirely present.
+Future<void> registerPushDevice(ApiConnection connection, {
+  required int deviceId,
+  RegisterPushDeviceKey? key,
+  RegisterPushDeviceToken? token,
+}) {
+  assert(key != null || token != null);
+  assert(connection.zulipFeatureLevel! >= 468); // TODO(server-12)
+  return connection.post('registerPushDevice', (_) {}, 'mobile_push/register', {
+    'device_id': deviceId,
+    if (key != null) ...{
+      'push_key_id': key.pushKeyId,
+      'push_key': RawParameter(key.pushKey),
+    },
+    if (token != null) ...{
+      'token_kind': RawParameter(token.tokenKind.toJson()),
+      'token_id': RawParameter(token.tokenId),
+      'bouncer_public_key': RawParameter(token.bouncerPublicKey),
+      'encrypted_push_registration': RawParameter(token.encryptedPushRegistration),
+    },
+  });
+}
+
+/// The parameters to [registerPushDevice] for setting a push key.
+class RegisterPushDeviceKey {
+  final int pushKeyId;
+  final String pushKey;
+
+  RegisterPushDeviceKey({required this.pushKeyId, required this.pushKey});
+}
+
+/// The parameters to [registerPushDevice] for setting a push token.
+///
+/// For constructing [encryptedPushRegistration], see [PushRegistration].
+class RegisterPushDeviceToken {
+  final PushTokenKind tokenKind;
+  final String tokenId;
+  final String bouncerPublicKey;
+  final String encryptedPushRegistration;
+
+  RegisterPushDeviceToken({
+    required this.tokenKind,
+    required this.tokenId,
+    required this.bouncerPublicKey,
+    required this.encryptedPushRegistration,
+  });
+}
+
+/// As in [RegisterPushDeviceToken.tokenKind].
+@JsonEnum(fieldRename: FieldRename.snake, alwaysCreate: true)
+enum PushTokenKind {
+  fcm,
+  apns;
+
+  String toJson() => _$PushTokenKindEnumMap[this]!;
+}
+
+/// The plaintext for [RegisterPushDeviceToken.encryptedPushRegistration].
+///
+/// See https://zulip.com/api/register-push-device#parameter-encrypted_push_registration
+@JsonSerializable(fieldRename: FieldRename.snake, createFactory: false)
+class PushRegistration {
+  final PushTokenKind tokenKind;
+  final String token;
+  final int timestamp;
+
+  PushRegistration({
+    required this.tokenKind,
+    required this.token,
+    required this.timestamp,
+  });
+
+  Map<String, dynamic> toJson() => _$PushRegistrationToJson(this);
+}
+
 /// https://zulip.com/api/add-fcm-token
 Future<void> addFcmToken(ApiConnection connection, {
   required String token,
diff --git a/lib/api/route/notifications.g.dart b/lib/api/route/notifications.g.dart
new file mode 100644
index 0000000000..2b053172b2
--- /dev/null
+++ b/lib/api/route/notifications.g.dart
@@ -0,0 +1,21 @@
+// GENERATED CODE - DO NOT MODIFY BY HAND
+
+// ignore_for_file: constant_identifier_names, unnecessary_cast
+
+part of 'notifications.dart';
+
+// **************************************************************************
+// JsonSerializableGenerator
+// **************************************************************************
+
+Map<String, dynamic> _$PushRegistrationToJson(PushRegistration instance) =>
+    <String, dynamic>{
+      'token_kind': instance.tokenKind,
+      'token': instance.token,
+      'timestamp': instance.timestamp,
+    };
+
+const _$PushTokenKindEnumMap = {
+  PushTokenKind.fcm: 'fcm',
+  PushTokenKind.apns: 'apns',
+};
diff --git a/lib/model/push_device.dart b/lib/model/push_device.dart
index 0b82b3c24a..8665dae22c 100644
--- a/lib/model/push_device.dart
+++ b/lib/model/push_device.dart
@@ -1,13 +1,23 @@
 import 'dart:async';
+import 'dart:math';
 
+import 'package:collection/collection.dart';
+import 'package:flutter/foundation.dart';
+
+import '../api/model/events.dart';
+import '../api/model/model.dart';
+import '../api/route/notifications.dart';
 import '../notifications/receive.dart';
+import 'binding.dart';
 import 'store.dart';
 
 /// Manages telling the server this device's push token,
-/// and tracking the server's responses on the status of push devices.
-// TODO(#1764) do that tracking of responses
+/// and tracking the server's responses on the status of devices and push tokens.
 class PushDeviceManager extends PerAccountStoreBase {
-  PushDeviceManager({required super.core}) {
+  PushDeviceManager({
+    required super.core,
+    required Map<int, ClientDevice> devices,
+  }) : _devices = devices {
     _registerTokenAndSubscribe();
   }
 
@@ -23,9 +33,78 @@ class PushDeviceManager extends PerAccountStoreBase {
     _disposed = true;
   }
 
+  /// Like [InitialSnapshot.devices], but updated with events.
+  ///
+  /// For docs, search for "devices"
+  /// in <https://zulip.com/api/register-queue>.
+  ///
+  /// An absent map in [InitialSnapshot] (from an old server) is treated
+  /// as empty, since a server without this feature has none of these records.
+  // TODO(server-12) simplify doc re an absent map
+  late Map<int, ClientDevice> devices = UnmodifiableMapView(_devices);
+  final Map<int, ClientDevice> _devices;
+
+  void handleDeviceEvent(DeviceEvent event) {
+    switch (event) {
+      case DeviceAddEvent():
+        _devices[event.deviceId] = ClientDevice(
+          pushKeyId: null,
+          pushTokenId: null,
+          pendingPushTokenId: null,
+          pushTokenLastUpdatedTimestamp: null,
+          pushRegistrationErrorCode: null,
+        );
+
+      case DeviceRemoveEvent():
+        _devices.remove(event.deviceId);
+
+      case DeviceUpdateEvent():
+        final device = _devices[event.deviceId];
+        if (device == null) return; // TODO(log)
+
+        if (event.pushKeyId case final v?) {
+          device.pushKeyId = v.value;
+        }
+        if (event.pushTokenId case final v?) {
+          device.pushTokenId = v.value;
+        }
+        if (event.pendingPushTokenId case final v?) {
+          device.pendingPushTokenId = v.value;
+        }
+        if (event.pushTokenLastUpdatedTimestamp case final v?) {
+          device.pushTokenLastUpdatedTimestamp = v.value;
+        }
+        if (event.pushRegistrationErrorCode case final v?) {
+          device.pushRegistrationErrorCode = v.value;
+        }
+    }
+  }
+
+  /// Generate a suitable value to pass as `pushKeyId` to [registerPushDevice].
+  static int generatePushKeyId() {
+    final rand = Random.secure();
+    return rand.nextInt(1 << 32);
+  }
+
+  /// Generate a suitable value to pass as `pushKey` to [registerPushDevice].
+  static Uint8List generatePushKey() {
+    final rand = Random.secure();
+    return Uint8List.fromList([
+      pushKeyTagSecretbox,
+      ...Iterable.generate(32, (_) => rand.nextInt(1 << 8)),
+    ]);
+  }
+
+  /// The tag byte for a libsodium secretbox-based `pushKey` value.
+  ///
+  /// See API doc: https://zulip.com/api/register-push-device#parameter-push_key
+  static const pushKeyTagSecretbox = 0x31;
+
   /// Send this client's notification token to the server, now and if it changes.
   // TODO(#322) save acked token, to dedupe updating it on the server
   // TODO(#323) track the addFcmToken/etc request, warn if not succeeding
+  // TODO it would be nice to register the token before even registerQueue:
+  //   https://github.com/zulip/zulip-flutter/pull/325#discussion_r1365982807
   void _registerTokenAndSubscribe() async {
     _debugMaybePause();
     if (_debugRegisterTokenProceed != null) {
@@ -38,12 +117,6 @@ class PushDeviceManager extends PerAccountStoreBase {
     _debugRegisterTokenCompleted?.complete();
   }
 
-  Future<void> _registerToken() async {
-    // TODO it would be nice to register the token before even registerQueue:
-    //   https://github.com/zulip/zulip-flutter/pull/325#discussion_r1365982807
-    await NotificationService.instance.registerToken(connection);
-  }
-
   Completer<void>? _debugRegisterTokenProceed;
   Completer<void>? _debugRegisterTokenCompleted;
 
@@ -90,4 +163,26 @@ class PushDeviceManager extends PerAccountStoreBase {
       return true;
     }());
   }
+
+  Future<void> _registerToken() async {
+    final token = NotificationService.instance.token.value;
+    if (token == null) return;
+
+    switch (defaultTargetPlatform) {
+      case TargetPlatform.android:
+        await addFcmToken(connection, token: token);
+
+      case TargetPlatform.iOS:
+        final packageInfo = await ZulipBinding.instance.packageInfo;
+        await addApnsToken(connection,
+          token: token,
+          appid: packageInfo!.packageName);
+
+      case TargetPlatform.linux:
+      case TargetPlatform.macOS:
+      case TargetPlatform.windows:
+      case TargetPlatform.fuchsia:
+        assert(false);
+    }
+  }
 }
diff --git a/lib/model/store.dart b/lib/model/store.dart
index e0b021a135..e0f9b588c2 100644
--- a/lib/model/store.dart
+++ b/lib/model/store.dart
@@ -628,7 +628,8 @@ class PerAccountStore extends PerAccountStoreBase with
       emoji: EmojiStoreImpl(core: core,
         allRealmEmoji: initialSnapshot.realmEmoji),
       userSettings: initialSnapshot.userSettings,
-      pushDevices: PushDeviceManager(core: core),
+      pushDevices: PushDeviceManager(core: core,
+        devices: initialSnapshot.devices ?? {}),
       savedSnippets: SavedSnippetStoreImpl(core: core,
         savedSnippets: initialSnapshot.savedSnippets ?? []),
       typingNotifier: TypingNotifier(realm: realm),
@@ -865,6 +866,11 @@ class PerAccountStore extends PerAccountStoreBase with
         }
         notifyListeners();
 
+      case DeviceEvent():
+        assert(debugLog("server event: device"));
+        pushDevices.handleDeviceEvent(event);
+        notifyListeners();
+
       case CustomProfileFieldsEvent():
         assert(debugLog("server event: custom_profile_fields"));
         _realm.handleCustomProfileFieldsEvent(event);
diff --git a/lib/notifications/receive.dart b/lib/notifications/receive.dart
index d501a5d97c..39849ef7d5 100644
--- a/lib/notifications/receive.dart
+++ b/lib/notifications/receive.dart
@@ -147,28 +147,6 @@ class NotificationService {
     token.value = value;
   }
 
-  Future<void> registerToken(ApiConnection connection) async {
-    final token = this.token.value;
-    if (token == null) return;
-
-    switch (defaultTargetPlatform) {
-      case TargetPlatform.android:
-        await addFcmToken(connection, token: token);
-
-      case TargetPlatform.iOS:
-        final packageInfo = await ZulipBinding.instance.packageInfo;
-        await addApnsToken(connection,
-          token: token,
-          appid: packageInfo!.packageName);
-
-      case TargetPlatform.linux:
-      case TargetPlatform.macOS:
-      case TargetPlatform.windows:
-      case TargetPlatform.fuchsia:
-        assert(false);
-    }
-  }
-
   static Future<void> unregisterToken(ApiConnection connection, {required String token}) async {
     switch (defaultTargetPlatform) {
       case TargetPlatform.android:
diff --git a/test/api/model/events_checks.dart b/test/api/model/events_checks.dart
index d29a7acb65..2a12303434 100644
--- a/test/api/model/events_checks.dart
+++ b/test/api/model/events_checks.dart
@@ -15,6 +15,14 @@ extension AlertWordsEventChecks on Subject<AlertWordsEvent> {
   Subject<List<String>> get alertWords => has((e) => e.alertWords, 'alertWords');
 }
 
+extension DeviceUpdateEventChecks on Subject<DeviceUpdateEvent> {
+  Subject<JsonNullable<int>?> get pushKeyId => has((e) => e.pushKeyId, 'pushKeyId');
+  Subject<JsonNullable<String>?> get pushTokenId => has((e) => e.pushTokenId, 'pushTokenId');
+  Subject<JsonNullable<String>?> get pendingPushTokenId => has((e) => e.pendingPushTokenId, 'pendingPushTokenId');
+  Subject<JsonNullable<int>?> get pushTokenLastUpdatedTimestamp => has((e) => e.pushTokenLastUpdatedTimestamp, 'pushTokenLastUpdatedTimestamp');
+  Subject<JsonNullable<String>?> get pushRegistrationErrorCode => has((e) => e.pushRegistrationErrorCode, 'pushRegistrationErrorCode');
+}
+
 extension RealmUserUpdateEventChecks on Subject<RealmUserUpdateEvent> {
   Subject<int> get userId => has((e) => e.userId, 'userId');
   Subject<String?> get fullName => has((e) => e.fullName, 'fullName');
diff --git a/test/api/model/events_test.dart b/test/api/model/events_test.dart
index 7cdfa94eff..b5824f567a 100644
--- a/test/api/model/events_test.dart
+++ b/test/api/model/events_test.dart
@@ -30,6 +30,40 @@ void main() {
     ).isEmpty();
   });
 
+  group('device/update', () {
+    final baseJson = {'id': 1, 'type': 'device', 'op': 'update', 'device_id': 3 };
+
+    test('push_key_id absent', () {
+      check(Event.fromJson({ ...baseJson }))
+        .isA<DeviceUpdateEvent>().pushKeyId.isNull();
+    });
+
+    test('push_key_id null', () {
+      check(Event.fromJson({ ...baseJson, 'push_key_id': null }))
+        .isA<DeviceUpdateEvent>().pushKeyId.equals(JsonNullable(null));
+    });
+
+    test('push_key_id an int', () {
+      check(Event.fromJson({ ...baseJson, 'push_key_id': 123 }))
+        .isA<DeviceUpdateEvent>().pushKeyId.equals(JsonNullable(123));
+    });
+
+    test('pending_push_token_id absent', () {
+      check(Event.fromJson({ ...baseJson }))
+        .isA<DeviceUpdateEvent>().pendingPushTokenId.isNull();
+    });
+
+    test('pending_push_token_id null', () {
+      check(Event.fromJson({ ...baseJson, 'pending_push_token_id': null }))
+        .isA<DeviceUpdateEvent>().pendingPushTokenId.equals(JsonNullable(null));
+    });
+
+    test('pending_push_token_id a string', () {
+      check(Event.fromJson({ ...baseJson, 'pending_push_token_id': 'ab12' }))
+        .isA<DeviceUpdateEvent>().pendingPushTokenId.equals(JsonNullable('ab12'));
+    });
+  });
+
   group('realm_user/update', () {
     Map<String, Object?> mkJson(Map<String, Object?> data) =>
       {'id': 1, 'type': 'realm_user', 'op': 'update',
diff --git a/test/example_data.dart b/test/example_data.dart
index 80c7cd8339..fd964aa6c7 100644
--- a/test/example_data.dart
+++ b/test/example_data.dart
@@ -95,8 +95,8 @@ Uri get _realmUrl => realmUrl;
 final Uri realmIcon = Uri.parse('/user_avatars/2/realm/icon.png?version=3');
 Uri get _realmIcon => realmIcon;
 
-const String recentZulipVersion = '9.0';
-const int recentZulipFeatureLevel = 382;
+const String recentZulipVersion = '11.0';
+const int recentZulipFeatureLevel = 468;
 const int futureZulipFeatureLevel = 9999;
 const int ancientZulipFeatureLevel = kMinSupportedZulipFeatureLevel - 1;
 
@@ -1353,6 +1353,7 @@ InitialSnapshot initialSnapshot({
   Map<int, UserStatusChange>? userStatuses,
   UserSettings? userSettings,
   List<UserTopicItem>? userTopics,
+  Map<int, ClientDevice>? devices,
   GroupSettingValue? realmCanDeleteAnyMessageGroup,
   GroupSettingValue? realmCanDeleteOwnMessageGroup,
   RealmDeleteOwnMessagePolicy? realmDeleteOwnMessagePolicy,
@@ -1414,6 +1415,7 @@ InitialSnapshot initialSnapshot({
     userStatuses: userStatuses ?? {},
     userSettings: userSettings ?? _userSettings(),
     userTopics: userTopics ?? [],
+    devices: devices ?? {},
     // no default; allow `null` to simulate servers without this
     realmCanDeleteAnyMessageGroup: realmCanDeleteAnyMessageGroup,
     realmCanDeleteOwnMessageGroup: realmCanDeleteOwnMessageGroup,