costs you $50 / yr to keep running.

After you buy your 4 tiles for $100, realize they are designed to not be chargeable. So, after a year or so, they will run out of power and you need to replace them for $50. Rinse, repeat.

Why not make the batteries replaceable? I guess mostly because you wont be forced into an upgrade cycle.

Jochen in Sydney about Tile - Find lost keys & phone