This is a really cool puzzle game idea. I'm not much of a puzzle game guy, so this bite sized chunk was the perfect size...for me. Although you introduced a new mechanic at the very end that I wanted to see how you used in future levels. I could see this being a really good, full featured game.
Push blocks to solve puzzles.
This is an enhanced port of a calculator game released in 2001. Produced by Detached Solutions, it was released as part of a collection of four puzzle games called PuzzPack. Here is a website about the original.
The latest update now includes an undo feature, new effects, and the full levelset from the original game.
Directions to move and push blocks.
A key (X button on console or on mobile) to undo, or hold it to restart the level.
X key (B button on console or mobile) to toggle Classic Mode, for visuals and effects more true to the original calculator game.
Not tested on mobile.