This app was mentioned in 4 comments, with an average of 1.00 upvote
Circa Infinity. Best game I've ever played. Been following it since the demo came out on PC and bought it day 1 on steam, now it's on phones and fantastic. They added a bunch of stuff in a huge update, including an infinite mode with six different difficulties and a TON of color palettes. Like... Over 50, maybe like 100. This is along with the normal 50 levels they had from the beginning.
This game is just so good I can't sing it's praises enough.