You can check [1] Sleep Cycle.
I'm using it mainly to track my sleep quality and to see my sleep patterns, but the app can wake you up when you're in the lightest sleep phase.
Unfortunately, I didn't use it extensively, so I can't give you adequate opinion on the wake-up function, but it's worth the try.
I was going to recommend sleepytime[1] to try and find a good time to go to bed at if you want to get up at 6AM. It looks like 10:30 is a good time though. Maybe try to find your sleep cycles and set your alarm for a time when you are not in deep sleep? There are some smartphone apps that are meant to help do this.
Re:Melatonin
by martythemaniak on Friday October 04, 2013 @12:02PM
(#6496133)
There's alarm apps that will let you set your alarm based on sleep cycles. If that doesn't work, you can try various sleep measurement devices to wake you up at the right time.
My biggest problem still is that my alarm at 6AM wakes me during my active dream cycle and most restful sleep. I'm not sure how to time shift that to meet my needs.
Any advice?