This. I was confused because I have definitely seen HR monitor casio watch years(10+?) before.

Garmin Instinct 3 Solar, very close to 30 days for me. YMMV depending on how much sun you get

My ideal watch also has: mobile voice & data connection (via eSim), speaker and microphone, camera.

Those in addition to what it already has: 1 month battery life, HR and SpO2 tracking, flashlight.

Also, blood glocose and BHB monitoring would be nice.

And I didn't mention the software..

It seems that the battery lasts 35 hours with heart rate tracking, 1 month with no HR, and 11 months with power saving.

    Run Time

    Using activity functions (heart rate): Approx. 35 hours max. 
    Using in watch mode with heart rate measurement OFF: Approx. 1 month
    Using with power-saving function ON: Approx. 11 months

Take a look at the Amazfit NEO. I use it with all the notifications off.

Very poor. Hardly lasts a week with step tracking and heart rate enabled. Like someone else mentioned, go for a Garmin instinct 2 or 3 solar. My 2 Solar lasts more than 30 days on a full charge.

36ish hours a charge w/ HR stuff enabled.

Amazfit Bip has you covered, you can disable notifications, you can buy used one for <20USD and they still last one month + they are perfectly readable in sunlight thanks to MIP display, I'm on my 3rd now

there is nothing better since Amazfit Bip, Casio came close, but they are too bulky

I can’t imagine a standalone heart rate monitor would be very useful without logging to a smartphone

It’s fashion. Don’t try to understand it.

They release collabs all the time with streetwear brands. They’ve released watches with PAC Man, stranger things, haribo gummies, Toyota, Honda, etc.

Chunky digital watches aren’t my thing either but Casio has carved out a very nice niche for themselves. They can essentially keep releasing the same designs with various colors and materials for decades.

And I do appreciate a solid, durable and accurate dumb watch sometimes. I have a couple analog/digital G-shocks that look very nice.

Personally I don’t understand the market for very expensive watches that are fragile, less accurate, need constant maintenance and look like nothing special for many thousands of dollars. To each their own.

I wear them. Sometimes it’s just fun to have a blocky, overly decorated thing on your wrist. Mostly I wear one for the utility I.e I’m doing something stupid where I might get hurt or wet or both and I really need to know the time.

They’re fun and functional. Childish? I hope that’s something that will never entirely fade in me. Pretending to adult all the time is exhausting

I believe it's pretty smart. Keep the core functions intact when the battery goes flat.

ProTrek series pioneered this "power stages" feature back in the day. The watch selectively powers down capabilities to keep core functions going for much longer.

I think it's nice that the watch falls back to effectively unlimited watch-mode instead of shutting down completely because the heart-rate tracker ate up all the battery.

You should google their gshock ring. It’s a mini Casio watch. Same style. Hilarious

They are well positioned for wearables certainly; but a phone play would be much too risky. Practically they would end up re-casing an existing phone which would never feel G-SHOCK.

Have you tried this open-source app:

https://github.com/izivkov/gshock-smart-sync-webapp

The HRM sensors are too big and need too big batteries. The popular ones even shun bluetooth to preserve battery though this feels more possible to me.

https://www.crowdsupply.com/oddly-specific-objects/sensor-wa...

Garmin watches indirectly measure respiration rate via HRV.

https://support.garmin.com/en-US/?faq=2yEgS0Pax53UDqUH7q4WC6

Is that even possible with medial grade wrist devices? Apple Watches can perform it only during sleep which makes sense. It seems like a difficult problem to solve without a chest strap, or just measuring during sleep.

The only other alternative I can think of is a screen strap (some companies make those screenless ones, Polar, Whoop) around the bicep, as it’s relatively close to the shoulder and chest areas which gently move with our breath.

You need a smart watch to tell you you are breathing?