Modified NFC Casio Watch
Modifications include; inverted black LCD, original watch face, new bright white LED, and NTAG213 NFC chip with 137 Bytes of usable storage.
You need to scan the NFC chip in exactly the right spot on the watch AND the phone. Best spot to scan is top right above the LCD.
NOTE: This watch is splash proof, NOT waterproof, so don't submerge it. It has also only been tested on Android, so I'm unsure about iOS compatibility