Wearable Devices Device GeneActiv Watch Mi Band E4 Wristband Fitbit Charge HR Angel Basis Peak iHealth Edge FitBit flex UP24 Flash (internal) ID 1 2 3 4 5 6 7 9 10 11 Manufacturer Activinsights Ltd. Xiaomi Empatica Inc. FitBit Seraphim Sense Ltd. Intel iHealth Lab Inc. FitBit Jawbone Misfit Readily Available April - May 2015 Available in the US Medically/FDA approved Image Bluetooth 4.0 Background Synching 3-Axis Accelerometer Heart Rate Skin Temperature Galvanic Sensor Extra Notes No public API, however, BLE protocol was hacked Exported in preprocessed form as JSON or XML. Public API Sleep Tracking Automatic sleep detection Raw Data Access RADAR applicable* Battery Life (Days) 30 - 45 30 1 - 1.5 5 7 4 5 - 7 5 14 ~180 Waterresistant Costs £190.00 £15.99 €1199.00 £904.62 £120.00 $99.99 £66.53 £199.00 $69.95 £46.54 £79.99 £99.00 $50.00 £33.27 Additional Costs £0.00 £0.00 €799.00/unit for 11 or more £0.00 $0.00 £0.00 £0.00 $0.00 £0.00 £0.00 £0.00 $0.00 £0.00 Total Costs £190.00 £15.99 €1199.00 £904.62 £120.00 $99.99 £66.53 £199.00 $69.95 £46.54 £79.99 £99.00 $50.00 £33.27 * qualifies for RADAR studies if used in conjunction with a smartphone to extract data related to speech, social connectivity and memory (-EMAs) .