Fossdroid get the popularity data (most popular and trending tabs) through Piwik API mostly elaborating the pageviews and the downloads.
In this way it’s possible to list the top 10 best apps/games viewed on Fossdroid.com (last 6 months):

  1. Yalp Store
    Download apks from Google Play Store
  2. DNS66
    Block ads/hosts via DNS
  3. WebTube
    Play YouTube videos
  4. NewPipe
    Lightweight YouTube frontend
  5. MaterialOS
    Material Design CyanogenMod 12/12.1 theme
  6. F-Droid
    Application manager
  7. Trycorder
    Upgrade your mobile device to a full-fledged tricorder
  8. Open Camera
    Camera App
  9. Mi Manga Nu
    Manga reader
  10. Simple Solitaire Collection
    Simple solitaire klondike game

As you can see the Yalp Store wins the battle: it allows Android users to download apks from Play Store without OpenGapps/others (you should create a fake Gmail account because this app violates the Play Store ToS).
The statistics regarding the total number of app-downloads of F-Droid could be/are different because Piwik elaborates the data from fossdroid site and only F-Droid knows the real stats (this explain why F-Droid is not in the first position).

Enjoy!

On F-Droid repository (catalogue of Free and Open Source Software applications for the Android platform) there are 2001 applications (~1420 also on Google Play) organized in 17 categories:

Category Count Graph
System 265
Multimedia 242
Games 221
Internet 217
Navigation 135
Science & Education 118
Theming 108
Time 104
Reading 104
Writing 94
Development 92
Connectivity 84
Security 68
Phone & SMS 53
Money 40
Sports & Health 35
Graphics 21

These apps have the source code in these sites:

Source site Count Graph
github.com 1589
code.google.com 124
bitbucket.org 53
gitlab.com 52
sourceforge.net 45
gitorious.org 18
launchpad.net 13
other 107

The most used licenses are:

License Count Graph
GPLv3 745
Apache2 414
GPLv3+ 231
MIT 204
GPLv2 113
GPLv2+ 79
NewBSD 36
GPL 22
AGPLv3 15
MPL2 14
WTFPL 13
LGPL 12
PublicDomain 12
FreeBSD 11
other 80

Hi guys,
we have a Blog! In my spare time I’ve fixed some issues and added a Blog to write about Android World: if you want to became a collaborator write me at .
I would like to take this opportunity to thank the awesome F-Droid team and the people who have taken the time to write me a mail.

Stay tuned!