The more I play with it the more I am getting to love it.
I have been using a PX3 for years and could wait for this to come out. Have the phone's rechargeable battery meant I did have to carry around a power supply or a butt load of batteries for the PX3.
Since I always have my phone, computer, and headset for work with me on the road. The UA was an ideal fit.
The UA is of plastic construction and very light and can get knocked around easily. Twice the size of other iRig interfaces but still small (two BIC lighters) Durable on all the bases it still performs after two years on the road. With the headphone output the volume can be adjusted on the UA to headphones, speaker, recording device, or Mp3 input of a car stereo for playing out in the boonies. The headphone output via computer will feed music with USB connection but not the case when connected via phone which, you will have to use the 1/8" input for music from the phone
Android app is free but limited compared to the iPxx app that you pay for and from reading reviews iOS owners seem to have a lot of issues; which I have not experienced with the UA and Amplitube UA. The is no landscape viewing like iPxx app which means you are scrolling to tweek an amp (which sucks). UI offer 4 slots, 1 each for Gain/Mod/Amp/Time effects; so you can't stack say 2 delays ect. but, you and move a effect pre/post in the amp chain. You can purchase amp packages (Fender/Marshall/Orange) the standard amp offerings are impressive but since the acquisition of Amplitube 4. I did add Soldano SLO-100 ...wish they offered a Mesa package and effects that are in the Amplitube app.
Amplitube app is great which has been mentioned already in Amplitube review. I will say this is where I notice a tiny bit of latency.
UA with amplitube sounds better say Line 6 pod products and modelers I own or have used, easier to use, and cheaper in the sense you already own a computer and taking that out of the equation. Keeping in mind you are not gigging but you think you are with it using it for Studio/Bedroom/Headphone use.