What a very interesting and unique concept. Much like other people, it definitely took me a minute to figure it out (I completely missed the guide menu in the main menu). Once I got going, it was quite a brain-teaser trying to think several steps ahead in order to re-form the numbers into the other side. It's also quite an interesting mechanic where you setup the right side of the equation, so in a way you can also strategize that way.
The only thing I really had issues with are the controls. They feel complicated and even after I familiarized myself I was still hitting the wrong buttons and what not.
But the game itself is quite the interesting and fun puzzler, definitely one of the most unique ones I've seen. Keep up the good work!