diff --git a/app/lib/services/connect.ios.test.ts b/app/lib/services/connect.ios.test.ts
new file mode 100644
index 00000000000..84e3a5f1e87
--- /dev/null
+++ b/app/lib/services/connect.ios.test.ts
@@ -0,0 +1,143 @@
+import { determineAuthType } from './connect';
+
+// Mock the isIOS helper to return true for iOS-specific tests
+jest.mock('../methods/helpers', () => ({
+	...jest.requireActual('../methods/helpers'),
+	isIOS: true
+}));
+
+interface IServices {
+	[index: string]: string | boolean;
+	name: string;
+	custom: boolean;
+	showButton: boolean;
+	buttonLabelText: string;
+	service: string;
+}
+
+describe('determineAuthType - iOS specific tests', () => {
+	beforeEach(() => {
+		jest.clearAllMocks();
+	});
+
+	describe('apple authentication when isIOS is true', () => {
+		it('should return apple when authName is apple and isIOS is true', () => {
+			const services: IServices = {
+				name: 'apple',
+				custom: false,
+				showButton: true,
+				buttonLabelText: 'Apple Login',
+				service: 'apple'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('apple');
+		});
+
+		it('should return apple when service is apple and name is empty but isIOS is true', () => {
+			const services: IServices = {
+				name: '',
+				custom: false,
+				showButton: true,
+				buttonLabelText: 'Apple Login',
+				service: 'apple'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('apple');
+		});
+
+		it('should return apple when name is apple even if service is different', () => {
+			const services: IServices = {
+				name: 'apple',
+				custom: false,
+				showButton: true,
+				buttonLabelText: 'Apple Login',
+				service: 'some-other-service'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('apple');
+		});
+
+		it('should prioritize oauth_custom over apple when custom is true', () => {
+			const services: IServices = {
+				name: 'apple',
+				custom: true,
+				showButton: true,
+				buttonLabelText: 'Custom Apple Login',
+				service: 'apple'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('oauth_custom'); // Should return oauth_custom first
+		});
+
+		it('should prioritize saml over apple when service is saml', () => {
+			const services: IServices = {
+				name: 'apple',
+				custom: false,
+				showButton: true,
+				buttonLabelText: 'SAML Apple Login',
+				service: 'saml'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('saml'); // Should return saml before checking for apple
+		});
+
+		it('should prioritize cas over apple when service is cas', () => {
+			const services: IServices = {
+				name: 'apple',
+				custom: false,
+				showButton: true,
+				buttonLabelText: 'CAS Apple Login',
+				service: 'cas'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('cas'); // Should return cas before checking for apple
+		});
+
+		it('should not return oauth_custom when custom is true but showButton is false', () => {
+			const services: IServices = {
+				name: 'apple',
+				custom: true,
+				showButton: false,
+				buttonLabelText: 'Apple Login',
+				service: 'apple'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('apple'); // Should continue to apple auth since oauth_custom condition fails
+		});
+	});
+
+	describe('other auth types still work when isIOS is true', () => {
+		it('should return oauth for facebook service', () => {
+			const services: IServices = {
+				name: 'facebook',
+				custom: false,
+				showButton: true,
+				buttonLabelText: 'Facebook Login',
+				service: 'facebook'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('oauth');
+		});
+
+		it('should return not_supported for unknown service', () => {
+			const services: IServices = {
+				name: 'unknown-service',
+				custom: false,
+				showButton: true,
+				buttonLabelText: 'Unknown Login',
+				service: 'unknown'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('not_supported');
+		});
+	});
+});
diff --git a/app/lib/services/connect.test.ts b/app/lib/services/connect.test.ts
new file mode 100644
index 00000000000..e1471e9a3bf
--- /dev/null
+++ b/app/lib/services/connect.test.ts
@@ -0,0 +1,304 @@
+import { determineAuthType } from './connect';
+
+// Mock the isIOS helper
+jest.mock('../methods/helpers', () => ({
+	...jest.requireActual('../methods/helpers'),
+	isIOS: false
+}));
+
+interface IServices {
+	[index: string]: string | boolean;
+	name: string;
+	custom: boolean;
+	showButton: boolean;
+	buttonLabelText: string;
+	service: string;
+}
+
+describe('determineAuthType', () => {
+	beforeEach(() => {
+		jest.clearAllMocks();
+	});
+
+	describe('oauth_custom', () => {
+		it('should return oauth_custom when custom is true and showButton is not false', () => {
+			const services: IServices = {
+				name: 'custom-service',
+				custom: true,
+				showButton: true,
+				buttonLabelText: 'Custom Login',
+				service: 'custom'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('oauth_custom');
+		});
+
+		it('should return oauth_custom when custom is true and showButton is undefined (not false)', () => {
+			const services: IServices = {
+				name: 'custom-service',
+				custom: true,
+				showButton: undefined as any,
+				buttonLabelText: 'Custom Login',
+				service: 'custom'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('oauth_custom');
+		});
+
+		it('should not return oauth_custom when custom is true but showButton is false', () => {
+			const services: IServices = {
+				name: 'custom-service',
+				custom: true,
+				showButton: false,
+				buttonLabelText: 'Custom Login',
+				service: 'saml'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('saml'); // Should continue to next conditions
+		});
+
+		it('should not return oauth_custom when custom is false', () => {
+			const services: IServices = {
+				name: 'custom-service',
+				custom: false,
+				showButton: true,
+				buttonLabelText: 'Custom Login',
+				service: 'saml'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('saml'); // Should continue to next conditions
+		});
+	});
+
+	describe('saml', () => {
+		it('should return saml when service is saml', () => {
+			const services: IServices = {
+				name: 'saml-service',
+				custom: false,
+				showButton: true,
+				buttonLabelText: 'SAML Login',
+				service: 'saml'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('saml');
+		});
+	});
+
+	describe('cas', () => {
+		it('should return cas when service is cas', () => {
+			const services: IServices = {
+				name: 'cas-service',
+				custom: false,
+				showButton: true,
+				buttonLabelText: 'CAS Login',
+				service: 'cas'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('cas');
+		});
+	});
+
+	describe('apple', () => {
+		it('should return not_supported when authName is apple but isIOS is false', () => {
+			const services: IServices = {
+				name: 'apple',
+				custom: false,
+				showButton: true,
+				buttonLabelText: 'Apple Login',
+				service: 'apple'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('not_supported'); // Should fall through to not_supported since isIOS is mocked as false
+		});
+
+		it('should return not_supported when service is apple and name is empty but isIOS is false', () => {
+			const services: IServices = {
+				name: '',
+				custom: false,
+				showButton: true,
+				buttonLabelText: 'Apple Login',
+				service: 'apple'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('not_supported'); // Should fall through to not_supported since isIOS is mocked as false
+		});
+	});
+
+	describe('oauth', () => {
+		const availableOAuth = ['facebook', 'github', 'gitlab', 'google', 'linkedin', 'meteor-developer', 'twitter', 'wordpress'];
+
+		availableOAuth.forEach(oauthProvider => {
+			it(`should return oauth for ${oauthProvider} service`, () => {
+				const services: IServices = {
+					name: oauthProvider,
+					custom: false,
+					showButton: true,
+					buttonLabelText: `${oauthProvider} Login`,
+					service: oauthProvider
+				};
+
+				const result = determineAuthType(services);
+				expect(result).toBe('oauth');
+			});
+
+			it(`should return oauth for ${oauthProvider} name even when service is different`, () => {
+				const services: IServices = {
+					name: oauthProvider,
+					custom: false,
+					showButton: true,
+					buttonLabelText: `${oauthProvider} Login`,
+					service: 'some-other-service'
+				};
+
+				const result = determineAuthType(services);
+				expect(result).toBe('oauth');
+			});
+		});
+
+		it('should use service as authName when name is empty', () => {
+			const services: IServices = {
+				name: '',
+				custom: false,
+				showButton: true,
+				buttonLabelText: 'GitHub Login',
+				service: 'github'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('oauth');
+		});
+	});
+
+	describe('not_supported', () => {
+		it('should return not_supported for unknown service', () => {
+			const services: IServices = {
+				name: 'unknown-service',
+				custom: false,
+				showButton: true,
+				buttonLabelText: 'Unknown Login',
+				service: 'unknown'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('not_supported');
+		});
+
+		it('should return not_supported for drupal (mentioned in TODO comment)', () => {
+			const services: IServices = {
+				name: 'drupal',
+				custom: false,
+				showButton: true,
+				buttonLabelText: 'Drupal Login',
+				service: 'drupal'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('not_supported');
+		});
+
+		it('should return not_supported for github_enterprise (mentioned in TODO comment)', () => {
+			const services: IServices = {
+				name: 'github_enterprise',
+				custom: false,
+				showButton: true,
+				buttonLabelText: 'GitHub Enterprise Login',
+				service: 'github_enterprise'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('not_supported');
+		});
+	});
+
+	describe('authName fallback logic', () => {
+		it('should use name as authName when both name and service are provided', () => {
+			const services: IServices = {
+				name: 'github',
+				custom: false,
+				showButton: true,
+				buttonLabelText: 'GitHub Login',
+				service: 'some-other-service'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('oauth'); // name 'github' should be used
+		});
+
+		it('should use service as authName when name is empty', () => {
+			const services: IServices = {
+				name: '',
+				custom: false,
+				showButton: true,
+				buttonLabelText: 'Facebook Login',
+				service: 'facebook'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('oauth'); // service 'facebook' should be used
+		});
+
+		it('should use service as authName when name is null', () => {
+			const services: IServices = {
+				name: null as any,
+				custom: false,
+				showButton: true,
+				buttonLabelText: 'Google Login',
+				service: 'google'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('oauth'); // service 'google' should be used
+		});
+	});
+
+	describe('priority order', () => {
+		it('should prioritize oauth_custom over other types', () => {
+			const services: IServices = {
+				name: 'github', // This would normally return 'oauth'
+				custom: true,
+				showButton: true,
+				buttonLabelText: 'Custom GitHub',
+				service: 'github'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('oauth_custom'); // Should return oauth_custom first
+		});
+
+		it('should prioritize saml over oauth', () => {
+			const services: IServices = {
+				name: 'github', // This would normally return 'oauth'
+				custom: false,
+				showButton: true,
+				buttonLabelText: 'SAML GitHub',
+				service: 'saml'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('saml'); // Should return saml before checking for oauth
+		});
+
+		it('should prioritize cas over oauth', () => {
+			const services: IServices = {
+				name: 'github', // This would normally return 'oauth'
+				custom: false,
+				showButton: true,
+				buttonLabelText: 'CAS GitHub',
+				service: 'cas'
+			};
+
+			const result = determineAuthType(services);
+			expect(result).toBe('cas'); // Should return cas before checking for oauth
+		});
+	});
+});
+
+// Note: Apple authentication when isIOS is true is tested in connect.ios.test.ts
diff --git a/app/lib/services/connect.ts b/app/lib/services/connect.ts
index 92ef4199746..7d8c448481b 100644
--- a/app/lib/services/connect.ts
+++ b/app/lib/services/connect.ts
@@ -464,11 +464,11 @@ async function getLoginServices(server: string) {
 }
 
 function determineAuthType(services: IServices) {
-	const { name, custom, showButton = true, service } = services;
+	const { name, custom, showButton, service } = services;
 
 	const authName = name || service;
 
-	if (custom && showButton) {
+	if (custom && showButton !== false) {
 		return 'oauth_custom';
 	}