iOS: Time lapse videos are great, but they can be hard to make. Not only are they time consuming, but you need to stabilise your camera and stitch photos into a video. Hyperlapse simplifies the whole process.
This app (from the Instagram team) lets you tap a single button to start recording. Hyperlapse includes digital stabilisation, so even if you're holding your phone in your hand, it will attempt to smooth the motion. It's not going to do professional work for you, but as a consumer-level product, it looks pretty neat. No word on an Android version yet.