https://androidrank.org/
Android Market Data | since 2011
Android market and Google Play data, history since 2011. List of android apps and android developers. History of android app installs, ratings and growth.
android marketdatasince
https://www.fsf.org/blogs/licensing/android-market-has-drm-too
Steer clear of Android Market and its DRM — Free Software Foundation — Working together for free...
free software foundationandroid marketworking togethersteerclear