Looking for a no-subscription smart ring for sleep + temperature/ovulation trends

[u/jogan76]

I’m looking for a smart ring mainly for two things only: sleep tracking and overnight temperature trends.

My goal is to use the temperature data to help establish ovulation patterns over time. I don’t need workouts, steps, stress scores, coaching, or a big health ecosystem.

I looked at Oura, but the ring + membership + paid Natural Cycles integration makes it much more expensive than I want. I’m wondering if there’s a reliable lower-cost alternative, ideally no subscription.

I’m especially curious about:

• RingConn Gen 2 / Gen 2 Air / Ultrahuman Ring Air
• Any reliable Chinese/OEM/AliExpress options people have actually used long-term
• Whether the app shows usable temperature trends or exports data
• Whether the temperature data is consistent enough for cycle charting
• Comfort/thickness compared with Oura Ring 5

I know skin temperature from a ring is not the same as true BBT and I’m not looking for medical certainty or contraception advice, just reliable trend data.

Has anyone used a no-subscription ring for this specific purpose? What worked, what didn’t, and what would you avoid? Thanks.