The blue Brightness tag lets you use changes in ambient brightness as a switch. It can notify you when the brightness changes, or check whether the brightness is within the range at the timing of some input. You can also check for nearby objects in front of the tag.
Specifications
Maximum external dimensions (width x height x depth) approx. 24 mm x 48 mm x 12 mm
Weight: about 13 g
Communication Methods Bluetooth Standard Ver. 4.0(Bluetooth Low Energy)
Maximum communication distance: Approx. 10 m
Li-ion battery with integrated power supply
External interface Micro USB (charging only)
App compatible OS/model: iPad 3rd generation or later, iPad mini, iPhone 4S or later, iPod Touch 5th generation or later with iOS 8.0 or later
Starting with Android 5.0, the Bluetooth standard Ver. 4.0 (Bluetooth Low Energy) on tablets and smartphones
Windows 10 Creators Update (1703) or later on devices with Bluetooth 4.0 (Bluetooth Low Energy)