For this achievement you must play and win 10 games in a row in One Session. Do not close the game or exit to your home screen, you can pause it and allow your phone to close/sleep though, just leave the app fully open.
I did this on the Easy - Fortress level and averaged about 3 minutes per game, I used UNDO 12 times and a reshuffle for the other achievement "Undo minimum 10 times and win" and it still counted.