Once you've placed your arrows, you can tap on any square and swipe in any direction.
Dmitry sent me a promo code to download his game. (Thanks Dmitry.) (I didn't realize it was a beta version. For the record, I try not to play-test beta versions only because it's too time consuming.)
The graphics are good. FLUD is HARD. I don't remember how many levels I solved, maybe 20?