A Moto phone with GrapheneOS and the "chop / chop" gesture[0] to turn on the flashlight would be a dream.

I'm, shamefully, an adherent to Moto hardware now because of that silly gesture. I use it multiple times a day. I had a friend with a late model Pixel try to replicate the functionality and he couldn't come up with a way to do it. It's silly, but it's too handy.

[0] https://en-us.support.motorola.com/app/answers/detail/a_id/1...

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nhubbard 3 hours ago | parent | next [-]

One of the important reasons that it works so well is because it uses the Hexagon DSP in the Snapdragon processors to catch the events. That's why it's so hard to replicate. It's possible to do it entirely in software, but it chews through battery if you do it that way. I can't find it now, but there was an article a few years ago that explained how the feature worked.

And there's no way to program the DSP without being the creator of the device because Qualcomm requires DSP programs to be signed, as far as I'm aware, and the key has to be trusted by the device vendor.

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EvanAnderson an hour ago | parent | next [-]

Wild. Thanks for the keywords to search-engine this with. I found "Reverse engineering the Motorola Sensorhub: Part 1"[0]. To this point I hadn't thought about how they might have implemented the feature. That article sheds some light on it.

[0] https://ristovski.github.io/posts/moto-sensorhub/

	▲	nhubbard an hour ago \| parent [-]
		That's the one!

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microsoftedging an hour ago | parent | prev [-]

This one? https://www.xda-developers.com/qualcomm-snapdragon-845-hexag...

	▲	nhubbard an hour ago \| parent [-]
		That's the right chip. The other comment shows off the article. I forgot that it was called the "sensor hub", that's why I couldn't find the post showing how it works.

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rkagerer 2 hours ago | parent | prev [-]

Neat. I wired the flashlight to a long press of the Bixby button on my S10+.

	▲	EvanAnderson an hour ago \| parent [-]
		I probably would have settled for a button, but the gesture is so nice. (There's also a "twist" gesture to activate the camera. It's also nice. I haven't ever gotten false positives with the gestures and they have become second nature. I never used any gestures before having a Moto phone and always thought accelerometer-based input was gimmicky and unreliable based on my experience with prior phones.)