Tablet Tracker - ESP32 Based

I designed a device for tracking when I last took my tablet as I have a dreadful memory. The device runs on an ESP32 C3 with a standard 0.96" 128x64 I2C OLED Display. The battery was harvested from a disposable vape but is a standard 13300 400mAh lithium cell. This is charged over USB C via a TP4056 module. I swapped out the R3 resistor on the 4056 for a 5.6k one to slow down charging thus prolonging cell life however you can exclude this step if you don't care about that. I also de-soldered the power LED on the C3 to improve battery life. The battery should be good for a few months as the ESP is put in deep sleep mode but I'm still testing this.

All in all the component cost is >£10 from sites like eBay ect.

I’ve included my code if you don’t want to write your own, all you need to do is put in your Wi-Fi name and password at the top in the WIFI_SSID and WIFI_PASSWORD fields.

The device syncs time automatically so accounts for daylight saving and so on. This syncs on startup but also every 24h at midnight. It is set to GMT but this can be changed by yourself.

Functionality wise, you press the button once to see the last reading and hold it down to record a tablet being taken.

The pattern on the front is recessed by 0.01mm so if you have a multicolour printer, just fill in the areas on your slicer and set the paint penetration layers to 3/4. If you don’t have one, leave them blank and the case will print fine without the pattern.