Great game, though the controls on mobile are a bit too imprecise.

As you drag a hole, the size widgets should disappear so you can better see what's around it. They could pop back up again once you're done dragging.

Personally I'd rather if you had to press a button or something (or long press?) to add a new hole. I keep accidentally adding new ones when all I want to do is adjust an existing one.

Also spamming the user with the help screen right off the bat is a bit much. As long as they know it's there and can pull it up / dismiss it, I think it would be more fun to sort of discover the game mechanics yourself.

Note several of the first 8 or so levels can be accomplished with a single minimum (8) sized black hole. Eg. I liked the simplicity of doing that on level 6.

I resisted playing on mobile until I got home, and you're absolutely right that it's a whole other experience on desktop. In terms of addictive potential this reminds me favorably of that Seedship game, it's very simple, but powerfully "just one more round."