Full disclosure, I didn't really want it and have plenty of other great training pouches. I got it because it was part of a bundle and the cheapest way to get the klimb and the traction mat was to buy the bundle that also included this pouch.
The closure doesn't stay open so when you grab a treat you must slide your hand into it and pop it open every single time. That's pretty annoying. Mesh pouch fits a modern smartphone, kind of, it hangs out the top a bit. The problem is the weight makes opening/closing the pouch annoying. Wouldn't recommend this as a phone storage bag at all. Has 1 more compartment in the back with a vertical zipper. Stuff will fall out of this so it's probably only good for some **** bags or maybe your keys.
The belt they provide is high quality and has a nice clasp. Good work there.
For $30 by itself I don't think it's worth it. With the bundle of klimb + mat, yeah it's not half bad there if you have no other training pouches.