Oregon Scientific BAR228HG Weather + Advanced Bluetooth Temperature & Humidity Sensor for Smartphone's and Tablet's Real-time temperature/humidity/weather forecast from Weather+ (per 15 min intervals), data history in curve (Temperature/Humidity/Barometer) Default Room Type Selection (10 room types) and pre-set alert setting/notification wording for desired room type Notification from apps (Reminder/ Alert) when you are within Bluetooth range when the weather data is out of the comfort level setting, can record 1 day/week/month/year weather record. Compatible System: iOS 7/8/9 above; Android 4.3 to 5.0 above LED indicator (Turn on/off, BLE pairing, data transmission, low battery) Powered by two (2) AAA batteries, included. Dimensions: 2.76 x 2.76 x 0.79-inches (H x W x D)