This is a fairly new guitar pedal. It allows you to choose from tons of different amps, pedals, & Fx (lots of them are based on popular amps and stomp pedals). You download the app to your phone and then you sync the sounds to your Xtomp. The first time you load a new effect it takes a little bit but after you have loaded an effect once it usually loads pretty quickly and it gives you the option to favorite your favorite effects. I have only had mine a couple of months and they have already added 24 new effects. I really like the distortion effects! There is one called Mafia (which is unique) that is perfect for ultra low (6-8 string) tuned guitars playing death metal. There is also another one I like called Metaland and while I think it is "inspired" by the Boss Metal Zone pedal it is way better and I can actually get a pretty good djent sound out of it. I am considering getting another unit because I rarely use any of the other effects because the distortions are so good. They recently added a looper but I can't get it to work right, there is always a little pause after your loop, so it doesn't function to solo over properly. All in all the Xtomp is little expensive for what it is but some of the sounds are top notch imho!