Help knock off works. but knock on does not.

[catchingup]

gentle double tapping the screen turns off the phone just fine.

But to turn on, I have to double tap hard. I have to jolt the phone.

Actually, I can turn on the phone by tapping the plastic on the side of the phone. I don't even have to touch the screen.

Anyone else having this problem?

 

[WarrantyVoider]

I think this is how it works. Turning off is triggered by double tapping on the touch screen. But with the phone in sleep/standby mode, the touch screen is off to save power and isn't used to detect tapping. So for the implementation of knock-on on this phone, I believe LG uses the vibration sensor (or accelerometer or whatever) to detect the trigger. In other words, you would actual double-"knock" on the phone as if you're lightly knocking on a wooden door. A tap is probably too weak to register as a knock. Once you learn how much/little force to use, the knock-on behavior should be mostly consistent. And since the touch screen is not involved for knock-on, you should be able to knock on any part of the phone. Note that with some protective cases, vibration is reduced so the effect might not be the same for everyone.

 

[Masterchief87]

I think this is how it works. Turning off is triggered by double tapping on the touch screen. But with the phone in sleep/standby mode, the touch screen is off to save power and isn't used to detect tapping. So for the implementation of knock-on on this phone, I believe LG uses the vibration sensor (or accelerometer or whatever) to detect the trigger. In other words, you would actual double-"knock" on the phone as if you're lightly knocking on a wooden door. A tap is probably too weak to register as a knock. Once you learn how much/little force to use, the knock-on behavior should be mostly consistent. And since the touch screen is not involved for knock-on, you should be able to knock on any part of the phone. Note that with some protective cases, vibration is reduced so the effect might not be the same for everyone.

You hit the nail right on the head with that one. It uses the accelerometer to detect sudden movement when the screen is off. Try using knock on to wake the phone when its sitting on a hard surface. The screen won't light up unless you hit it hard enough to make it bounce!

 

[WarrantyVoider]

Yep. When the phone is lying on a hard surface with the screen side up, it might be easier to hit the home button instead. If you can pick up the phone and the phone is in a protective case, another possibility is to pick up the phone and lightly tap/knock the hard surface with a corner or edge of the phone. Not necessarily easier than hitting a button, but no need to know the orientation of the phone to locate its button. And if you're holding the phone, like when you just take it out of your pocket, you can lightly tap/knock the back of the phone with the fingernail or knuckle of your index finger. Again, not necessarily easier than pressing the power or home button, but with knocking, no need to perform finger gymnastics to reach a specific spot on the phone.