After just three weeks of work on their startup, two students on the innovation design engineering course at London's Royal College of Art won a place on Y Combinator's prestigious accelerator program. Their fitness gaming startup, Quell, is built around a low-cost wearable made of smart resistance bands that tracks users' combat-style workouts as they fight through a fantasy game on their phone or laptop. Quell has raised $150,000 in investment from Y Combinator, as well as funding from a series of angel investors, including Twitch's Kevin Lin and AngelList cofounder Naval Ravikant.