Key Features Heart Rate Monitoring Polar Telemetry (optional chest strap required). Lifepulse Digital Heart Rate Monitoring with DSP (Digital Signal Processing) Quick Start Remembers your preferred walk, jog and run speeds, as well as three incline position Screen Size Treadmills 19 in (48 cm) Bikes/Cross-Trainers 16 in (47 cm) 10 in (25 cm) Device Compatibility Android TM, iPhone®, iPad®, iPod® Android TM, iPhone®, iPad®, iPod® Number of Workouts Up to 42