This app was mentioned in 3 comments, with an average of 1.00 upvote
I'm PRETTY SURE this is the app I have: https://play.google.com/store/apps/details?id=com.spring.bird.game2048plus&hl=en
(Who knew there were that many apps called "2048 plus"?)
I have no idea if it's updated or whatnot because I've had it for at least a year; since the craze... maybe longer than a year. In fact I updated to a new phone but I still keep my ancient galaxy I around for this game, because I can't import it to iOS.
Here's an online variant: http://2048game.com/variations/8x8.html
It is this one: https://play.google.com/store/apps/details?id=com.spring.bird.game2048plus
Intended for 2048 players who feel this game is not necessarily about speed.
This is the app I'm playing on