We all want to train our brains, learn another language or practice a skill, but struggle to find the time. UnlockYourBrain solves that problem: it's an Android app that replaces the "slide to unlock" lockscreen with a small, unobtrusive math or vocabulary puzzle. Our customers - we have 300k installs, and 30k daily active users - range from parents to retirees, but all don't want to waste the two seconds it takes to unlock their phones.