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Made by Rolling Square -- the company behind the really cool inCharge X, 6-in-1 charging cable -- Tau is designed to keep your smartphone charged up and your keys in one place.
Tau is a tiny power bank key fob that magnetically attaches to a wall-mounted charger. In the morning, you grab your keys along with a fully-charged power bank. When you come back in the evening, you pop your keys back in the holder and charge up the power bank.
This way, you know where your keys are, and you always have a charged-up power bank.
Here's the fob in the charging dock, with the dock charging cable attached. It's a neat package.
Tau is everything I expect from Rolling Square -- a quality product that actually solves a real problem. A tiny power bank disguised as a key fob and a well-mounted charging dock turns this from what might be considered a gimmick into a useful tool.
This is perfect for people who forget where they've put their keys and run out of the house in the morning with a smartphone that's almost dead.