I came here wanting to know the same. It seemed pretty cheap and actually shows spin direction on the pitch. Wondering if anyone knows how accurate it is. If it works I feel like I should have held off on the revfire.
I've purchased the pitch tracker about two weeks ago and posted my results in "another tech ball to put on our Christmas list?" on this forum (Last post was Nov. 29). Ball quality is good and it seems perfectly balanced but you do need to charge it occasionally, unlike the Revfire. What I can tell you is that I tested with my DD and she threw 10 Fastballs, 10 Rise and 10 Changeups. All the changeups registered a spin rate and spin direction. Of the 20 fastballs and riseballs, only 14 registered a spin rate and only 7 of 20 registered a spin location. The initial testing was done in my basement at about 40 ft. I meant to update the results from a gym session last week but my buddy broke a window on the second pitch so I put the ball away and pulled out my jugs softie when the custodian investigated Spin rate and spin direction are only available with a $10 / month subscription (damn fine print!) but it comes with a 14 day trial. The spin rates seems pretty accurate but from my perspective, the spin direction is 2D only and gives you reading from a clock (i.e. 6:27) and a visual. I'm hoping that they plan on adding a 3rd dimension to the readout but the site has been down for two weeks so I can't find any information on it. I'll post an update next time I get the ball out in a bigger area. It's a little cold here in the north to pitch outside!
All the data is transferred after each pitch to an app on my iphone. Not sure if they support android or not.