Levels 1-10 are currently out for free. My goal is 200 levels. My intention is to release a new version every 10 levels.

Starting with the release of level 20 new versions will be free for a limited window of time, and then increase to $20.

I might increase the price later on after a few releases we will see, but for now that is the plan.

I intend to let the demo remain free forever.