Nov 16, 2015

16254.1: padlock button to lock slide to body; new scales: 1/(πx) (CIF/DIF), acos° < 8°, √x and √10x (R₁ and R₂), separate asin and atan; long-tap on scales no longer brings up useless legacy message; new 3D-style app icon.

15919.0: support action bar on post-Gingerbread systems; fix one source of crashes; colour-code descending scales in help; drop support for Android 2.1 because of crashing system bug.