FluidMath

My son is a gonna lose his mind over this. It's like the children's version of Mathematica with Digital Ink support. It simplifies handwritten fractions, solves handwritten equations, graphs with a gesture of the pen, modifies variables with gestures, and even has some cute animations to visually demonstrate physics problems. One hang up: Maybe I'm missing something but the eraser doesn't seem to work, but scribbling-to-erase works fine. Otherwise, it's an Insta-buy for me.

Hidden $15/year fee for inability to save worksheets. That alone makes this app nothing more than a gimmick. Also animations crash if y resolves to a negative number!? Why not just handle negs by not moving object until 'y' is positive? Can't model any situation where one object moves before the other. This app should not be treated as more than a proof of concept for a potentially amazing application! App would be 3.5 stars with save/open feature. A 3 if the Animation didn't crash. A 4.5 if both were addressed. A 5 if it was cheaper and all complaints addressed. Hope this helps someone...

The app is in a continuous state of a trial until you buy a yearly service plan which is way over priced. the cost is also hidden until you actually go through the purchase process. It has great potential. A fixed cost that is posted up front would be more appealing.

Need more time for trial like 30 mins

Not sure why... I would like to see a step by step answer presented with the answer. The answer isn't so helpful if you don't understand how it was derived.

Surface Pro 4, Anniversary Update. The opening screen shows for about two seconds, and then the app shuts down. I uninstalled, did a two-button shutdown, then reinstalled. Same result.