The F-Droid Repository is an easily-installable catalogue of free and open source apps for Android. With F-Droid, it's easy to browse and install apps on your device, and keep track of updates. You can also browse the repository with a web browser, and download the app directly from there, if you can’t or don’t want to run the F-Droid client on your device.
- APK pure offer a variety of applications, almost all that you can and can't find in Google Play Store. F-Droid is a specific store that offer open-source applications. If you didn't find an app on the Play Store because of your location (like Supercell apps, Warner Bros apps) for sure you won't find them on F-Droid.
- just open source stuff that is free anyway