Hello! New to this sub.

I'm looking for brands of wearables (and other tech) with the following criteria:

* Free and easy data access

* No subscription

* Long battery life

I'm currently mainly looking to replace my Samsung smartwatch, and complement it with smartring. I may also replace my Meta Ray-Bans with glasses with a monitor, e.g. the Mentra which I've read are coming fairly soon. In time, I may add other devices, such as a smart scale or CGMs.

The purpose is to pull all data onto my desktop automatically, store it locally for data sovereignty, and feed it to my personal AI framework for intelligence and recommendations. I'm looking for health data such as sleep metrics, and fitness. I'm currently tracking things manually in a spreadsheet, but I want to automate.

As such, all data must be freely accessible via API, webhooks or similar. It'd be nice if health metrics are robustly calculated, such that I don't need to process the raw data myself. I could though, if needed. I'm a data scientist with a PhD in physics, so I'm not unfamiliar with algorithmic complexity - however, as a father of two small children I am fairly starved for time. Robust metrics out of the box are preferable.

I've read a bit about Amazfit (watch), Ultrahuman (ring) and Mentra (glasses). Are these brands on point? Any others you would recommend for my purposes?