I am thinking of building a second revision of my "Tap Badge" project, a small wearable I would like to use as general purpose interface with my smart home and other projects.
I am currently facing a bit of a design problem: How do I get internet onto it?
My current option would be to buy a U-Blox module for cellular internet connection, get a cheap IoT Sim Card with a few MB each month, and use MQTT. However, this would be quite a power drain and I wouldn't be able to use nearby WiFi, unless I also throw an ESP or similar onto there.
I might be able to add Bluetooth to my system and use BLE - this would be the preferred option since it can then use my phone's internet. I have tried this in the first revision, but I really disliked how problematic it was to keep my DIY app running in the background. Android loves to kill these things, which would sever my connection.
Here's my question: Has anyone of you done something similar, so I can take some inspiration from it?
Or does anyone know of an app that does this for you, i.e. it provides a bridge between a BLE Service and a internet connection like MQTT?