coloring books have been around for ages. however, the idea of adults doing them to relieve stress is a fairly new concept. these days, it’s more or less apropos to kids and adults alike to crack open a coloring book. there are tons of coloring book apps on android. admittedly, this genre could use a little work. even so, there are some pretty decent ones that should be a lot of fun. here are the best coloring book apps for android!