The newer straps speak almost the same language as the WHOOP 4 we researched in Parts 4–6. Almost. The handshake byte changed, the framing grew, and the one command that would have

The WHOOP records all night and uploads nothing until you ask. Here's what's actually in that buffer, the field map that everyone — me included — got slightly wrong, and the

Six nights, 356,000 records, thirteen algorithm variants, and a surprisingly honest answer from the data. In the previous posts we broke into the WHOOP's proprietary BLE protocol, built a passive

How a Raspberry Pi, two Nordic dongles, and a carefully-timed Bluetooth toggle revealed a protocol variant that no public documentation mentions. The WHOOP is a fascinating device to reverse-engineer because it

After a chest strap that leaked its ECG by accident and a band that hid everything behind one undocumented byte, here's the device that just tells you how it works, and