Wrist detection

[jackdur]

Please add wrist detection – functionality to detect when the watch is/isn't on the wrist. This probably requires an algorithm that uses the heart rate sensor and is at the same time enough but not too sensitive to detect the loss of led return reflect.

Wrist detection is needed to automatically lock the watch with a password when you take it off.

[mark9064]

Sorry I forgot to comment on the original issue(s) - feature requests are tracked in discussion posts so I've converted both of your issues over - we've found the discussion board works much better for fleshing out ideas, hope this is ok :)

[jackdur]

Absolutely, thank you! :)

Btw what do you think, is this feature possible to implement in InfiniTime?

[mark9064]

It's hard to say, there is quite a bit to consider
Should this feature exist at all? Does InfiniTime have sensitive data worthy of locking the device?
What are the semantics of locking? Which features should be disabled? Does it justify the extra complexity and code churn to have a locked state? Same goes for having a separate path for polling the heart rate sensor.
Is sensible locking actually possible with the heart rate sensor? - this one I can at least offer an opinion on: I'd say maybe. The sampling rate might have to be high enough to drain the battery noticeably. Also, tuning for different skin colours will make testing more challenging. Otherwise it's probably possible to set the HRS on a long delay and trigger some event if the value falls below a threshold for some number of readings.

[liamcharger]

I don't think it'd be very practical to use the HR sensor to achieve this.

There are two reasons I would want this to be implemented: it would allow the watch to stop measuring heart rate when the watch isn't on the user's wrist (which would defeat the purpose if we use the HR sensor to check) and we'd be able to allow the companion app (InfiniLink) to check if it should send info notifications (low battery, goal achievement, etc.) or to just send them to host device.

Using the accelerometer to measure if it's being worn or not could be an idea (??), but it wouldn't be ideal as if the watch was moved around (picked up, etc.) it would register as being worn again, and if the user was asleep, etc., it would be registered as not on the wrist.

[ForeskinJim]

The Galaxy watch determines if it is worn via the HR sensor and can confirm it is both annoying and a battery drain. There had been a few times where I left the watch face down before bed and just as I'm about to fall asleep my room is bathed in a green strobe light.

I think the combination of the two could work to check if the watch has been set down. If the acceler. detects a sudden stop with no further movement it can ping for life with the HR sensor and if it detects nothing it wont check again until the watch starts moving.

Like @mark9064 said though I don't know if there's really a point. If someone steals your watch and you're worried about them possibly reading your texts, you can just turn off your companion app. Then again unless you're worried about someone in your household or workplace I don't think anyone who steals your watch is going to hang around.