EmbeddedHash

I would suggest using either an Arduino w/ BLE shield or a raspberry pi pico w. Both platforms have great SDKs and a lot of online support/community. Raspberry Pi pico supports circuitpython if that is the route you want to go (i.e. if you are more familiar with python). But most embedded software is written in C/C++.

Not sure if I understand, but you currently have a device that has UART enabled, and you are trying to communicate with it via BLE? Thus, you want to add a BLE chip, i.e. the nrf52, and then relay the commands from BLE -> UART for the second chip?

Regardless, Zephyr is an RTOS which provides OS functionality like scheduling, interrupt handling, semaphores, etc.

It is most likely overkill for what you are attempting to do. You should instead look at the vendor provided SDK for the nrf52 chip and program it bare metal. The SDK is most likely just libraries/drivers and does not come with an RTOS.

In my opinion, the best way to treat something is to first understand the why before attempting to fix it with the what. Try and have her understand why her hip is hurting. Is it pain radiating from her bone(s), or from the ligaments, tendons, muscles, etc in the area. A couple things I would suggest she focus on. 1. Daily exercise, such as walking at least 1 hour a day, is crucial. It increases blood flow to the lower body, lubricates joints, etc. 2. Another crucial and very neglected form of activity in western society is stretching/yoga. Make sure she is stretching daily, preferably after doing some sort of exercise like walking so that the muscles are warm and more malleable.

Yep. Another suspect of this is cooking oil spray, like Pam. They can advertise very low calories, usually 0, per serving but a serving is considered like 1/3 of a second spray.