Whoop won't sell you the strap. There's no device price on the site, just a $199 to $359 a year membership with the hardware bundled in, because the whole business is the software layer, the recovery and strain analytics that were supposed to be too hard for anyone to rebuild. One developer rebuilt them. He reverse-engineered the strap's Bluetooth protocol, recomputed recovery, strain, HRV and sleep locally in a SQLite database on your own phone, and shipped it as a free app called NOOP. No…