Postural takes a front and a side photo, measures your posture on the device with Apple's Vision framework, and turns it into a Postural Age: your real age plus a penalty of up to 8 years. It measures five markers and scores only the two with published evidence behind them. The other three are shown and count zero. A licensed physiotherapist reviewed the routines, the form cues and the scoring thresholds. Photos never leave your phone. The scan, the number and the coach note are free.