Night Clock app

Hello, I developed this app as I discussed an issue with a friend of mine, a blind guy. When he wants to know the time, he has to launch a vocal announcement. This can bother other people in night time. So I put up this thing, that just vibrates. Tell me please what you think and if it is possible to improve it (for example the text in the credits part can be improve for shure).
Here aia and apk files
NightClock.aia (266.1 KB)

Why does *.apk file not load?