Actually released a few days ago, I was rather amused to see several developers trying to sell commercial utilities to auto-lock (as in 'keypad lock', rather than full 'enter lock code' each time) your smartphone. Why pay when Autolock is 100% free and works brilliantly?

(I was actually considering a review of Autolock, but as it's tiny, utterly simple and works, it would have been the shortest review of all time!)