This alarm clock is similar to the standard alarm clock built from my Android phone and use. He has different sleep modes and volume settings, such as a gradually louder expectant alarm or also music or melody, a timer and a stopwatch (it can be installed later free). My purchase decision was above all the fact that this alarm clock can be programmed via the voice control Alcoid. My standard alarm clock could be true also program by voice control, but "rang" he always without sound. That brings me, of course, then nothing: o There are of this alarm clock is also a free app, but with commercials that are sent attached with the "Stop" button, so you may even call one or the other advertising display when you turn off the alarm ;-) The paid version is not very expensive and ad-free. One reason to buy this app.