It allows you to download after registering ( without a fee) and you can download scores form the Musescore archive of sheet music that is free of charge and includes around ten thousand scores and downloads fast and once downloaded they are in your device.
So it is one interesting thing to this reader is that you can buy a cheap USB pedal and if your phone can support a USB-OTG cable you can switch pages with your foot. If this existed for guitar scores I would be all on it! As that would be very convenient.
It has similarities with the Musescore player application but with less function but on the other hand this one is for free and the developer is promising more functions. The first one being that you will be able to photograph score sheets.