I just noticed that the Android SDK is now non-free software. If you go to

https://developer.android.com/sdk/index.html#download

and click on one of the files, you are presented with lengthy “Terms and Conditions” which for example say:

In order to use the SDK, you must first agree to this License Agreement. You may not use . . . → Read More: Android SDK is now proprietary, Replicant to the rescue