Track Explorer is a program which helps you exploring your GPX tracks.
It is build with the help of the Eclipse Rich Client Platform, making heavy use of the Java 8 Stream API.
Display only the tracks which pass through a particular region. 
Select several tracks to be shown at once. 
https://github.com/HenrichN/trackexplorer/releases
Mac: Open preferences by clicking on Track Explorer -> Preferences.
Windows: Click on File -> Settings.
Add a location by clicking on New. All files ending on .gpx in this location will be added.
Click on Geo Search. A rectanlge will appear. This is the region a track must pass in order to be included in the results.
You can move and resize the region.
To start a search, click on Go.
Reset will create a new rectangle on the center of the screen.
To disable the search, click on Geo Search.
Just type in the box above the track list. The tracks will be filtered according to the input.
To select a track for permanent display, right click on the trick and select Add track permanently. The track will move to the list in the bottom.
To stop displaying a track permanently, select the track in the bottom list and press delete.
To be able to do multi-platform builds, please have a look at: https://wiki.eclipse.org/Building#Preferred_way_of_doing_multi-platform_builds