This App is a part of a Do-It-Yourself project: Build your own Smartwatch with a bluetooth UART interface, Firmware and Circuit. The Circuit uses low cost parts: Arduino Pro Mini, a HM-10 (CC2541) or Bluefruit LE UART friend or nRF51822-04AT serial bluetooth module and a monochrome oLED SSD1306 display (128x64 pixel). Firmware and circuit are modified for a low cost version.
The UART Smartwatch App is the non-mini App (master branch on github; "mini" is the gplay branch). You find UART-Smartwatch on http://f-droid.org and an APK on github.
## The Firmware
You get the Arduino-IDE file from github: https://raw.githubusercontent.com/no-go/UART-Smartwatch/gplay/UART-Smartwatch_firmware/UART-Smartwatch_firmware.ino
* blinking LED, if a new notification is present
* 250 chars notification buffer (Display needs so much dynamic RAM)
* Button 1: get a fresh time and the notification buffer from your smart phone
* Button 2: display the time and power level for 4 seconds
* Button 2 (press for more than 4 seconds): switch to a different time mode
* runs for more than 6h (first and second time mode)
## Time Modes
* Digital (4sec)
* Analoge (4sec)
* PipBoy Design (4sec)
* Digital for ever
Attention: You need a serial USB device (less than US 4$) to store the firmware on the ProMini chip. You need a small circuit (less than US 1$ on aliexpress) to load the Lithium polimere akku (Lipo).
I publish everything under the free BSD-3 License.