ive used an app called "gentle alarm" ever since I got android about a year and half ago, and it's GREAT!
it can do what you're asking for plus my favorite feature is a setting that will slowly fade in an alarm (i used music, it picks a random song out of the 4,000 or so i have on there)
you can have a specific alarm schedule as well, (set it to play only on certain days of the week) which is what i do for work, so i never even have to set my alarm! it knows not to go off on my days off.
there is also a setting to reduce the snooze time each time you press it by whatever number you want. in other words if you reduce by 5 min for example and your first snooze is 20 minutes, then the first time you hit snooze it will be 20 min, the next 15 min, the third time 10min, etc.
there is also a safe alarm if you wish to enable it which will play a loud, obnoxious alarm if you sleep through the normal one.
you can also do a "quick alarm" which i use for napping. you can either set an alarm on a timer "in hh/mm" or at a spefic time "at hh/mm"
All these things are OPTIONAL and everything is super customizable!
the app is only 2.99 and well worth it in my opinion!
