What is Bluetooth Low Energy (BLE)?
To save battery usage, to have longer battery life.
“Bluetooth low energy is a brand new technology that has been designed as both a complementary technology to classic Bluetooth as well as the lowest possible power wireless technology that can be designed and built. Although it uses the Bluetooth brand and borrows a lot of technology from its parent, Bluetooth low energy should be considered as different technology, addressing different design goals and different market segments.”
by Robin Heydon <Bluetooth Low Energy, The Developer’s Handbook>