An extremely well-thought-out app. Includes a built-in comprehensive help document for rules  instructions  and controls. Includes arrow controls for certain games where precision may be difficult on small screens. The seed and puzzle sharing utility is a welcome addition. Looks professional enough  though material design would admittedly be nice. This one free app is like several apps in one  in a package so well-presented that it's worth money  but is instead free as in gratis and free as in beer. A must-have.
December 17 2016