I made a light alarm. Used a digital plug in timer and a really bright white/high temperature kelvin bulb to simulate bright sunlight. Set it to come on 30 min after sunrise. That was 5am in my area in summer.

It made me sleep significantly worse. I felt like I was being audited and judged while sleeping so when I was tempted to switch sleeping positions I knew it would know so I would hold still.

I prefer to just use this instead now: http://www.youtube.com/watch?v=BrfAWHHVz50

I used the sleep cycle alarm last night because I saw this question. I did get a good night sleep but I think that has a lot to do with making the room dark and going to bed at a good time. I like the app because it tracks your movements (I didn't find it inhibitory at all) and recorded the sounds I made (Snoring, talking, alien séance). I'll continue to use and evaluate it. Since we are slowly waking up the fact that sleep is the most important thing for us biologically (god I love puns), I expect more and more people to use apps like this. Sleep for Droid coupled with the Sleep Stats app is awesome.

I used the cell phone app, but found that it could not identify my sleep levels (it showed no change in sleep phase throughout the night). I suspect the that the accelerometer failed to detect my motion. If the app is free, give it a try.

I occasionally use an app on my phone that uses an accelerometer to calculate how much I move in my sleep and therefore what part of the sleep cycle I'm in. As long as I calibrated it correctly to my sleep habits (and different beds), it worked pretty darn well - but you do have to keep your phone ON the bed right next to you. I almost always woke up feeling rested, and it was nice to have some data on my sleep cycles. Not entirely sure how accurate that data is, though...

I stopped using it because I no longer have the free time to have a huge wake-up window. (I could set a smaller wake-up window, but then it's much less likely to wake me up at the right time in my sleep cycle)

I have ElectricSleep. I have used it a few times and I think it works pretty well on my newer phone. I have mine set for a half hour wake up window and haven't had any problem with it. You just have to be sure to calibrate it properly and have your phone right next to you on the bed. I wouldn't pay for it, but as a free app it's pretty cool. I also have Lightning Bug, a white noise app, and I swear by it since I'm a super light sleeper.

Any updates / new reviews on this application? I have recently installed it and think it is pretty darn sweet, but am curious as to others thoughts.

I use a Zeo and it has this type of functionality built in. In the end, I wake best when I use no alarm at all. So I don't find the alarm too useful.

However, I can definitely notice a difference in how I feel in the morning depending on whether or not I wake to an alarm mid-REM or naturally.