I tried (The Alarm Clock Rio free) and I found it beneficial, especially it has couple alarm sounds that can wake you up even if your sleep is kind of deep, I had another alarm before but the sounds are weak and not strong, so I recommend this app to the users, and I suggest from the developers of this app to change the settings to make the sounds increasingly go higher,but at the end I am satisfied with the free version because I have what I want.
IHobby about Alarm Clock Rio Lite