It's a Zendrum. www.zendrum.com
Level 35 with some practice.
It then froze up on me every time I clicked to make a new ball.
Yeah, mine locked on level 39. 96706.
The secret is never move. Just make balls in the upper left corner, watching for where you will get hit from. Right before a hit, release and immediately reclick. The top and left wall keep you safe, the bottom is your own discs. Just keep doing it.