Android App, Firmware and Circuit for a DIY Smartwatch working with Bluetooth Low Energy (4.x)

Features:

Press Button 1.5 s : sync the time between watch and phone. Show date and notifications as scrolling chars.
Press Button 0.5 s : show the time calculated by the watch. Show the battery level and an analog clock
small analog clock
digital clock
Battery Level
about 18 hours with LiPo 3.7V (170mA)
some emoticons works
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