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[Q] Ways to use torch with minimal battery use

OP firesword14

3rd May 2014, 10:31 AM   |  #1  
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So this is a 3 part question on Torches

1) Is there any way to operate torch when your phone is off, basically to be able to use your torch while your phone is off, so that your torch is the only thing utilising battery and not the system, this for incase of emergency. If it is not possible to use the torch when your phone is off, can we use it when the phone is in deep sleep? basically my target it to use the phone as a torch while using the most minimal amount of battery.

2) On Xposed there is an app by wanam - Xposed torch, it allows you to use the torch without turning on the screen, now is this particular app waking the device from sleep or not?

3) For worst cases scenarios can we flash a system which only allows the torch to run via the buttons and nothing else, like this can be used via multirom and save battery
3rd May 2014, 05:10 PM   |  #2  
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Quote:
Originally Posted by firesword14

So this is a 3 part question on Torches

1) Is there any way to operate torch when your phone is off, basically to be able to use your torch while your phone is off, so that your torch is the only thing utilising battery and not the system, this for incase of emergency. If it is not possible to use the torch when your phone is off, can we use it when the phone is in deep sleep? basically my target it to use the phone as a torch while using the most minimal amount of battery.

2) On Xposed there is an app by wanam - Xposed torch, it allows you to use the torch without turning on the screen, now is this particular app waking the device from sleep or not?

3) For worst cases scenarios can we flash a system which only allows the torch to run via the buttons and nothing else, like this can be used via multirom and save battery

Do you need it to use the camera flash? In other words, does it need to be as bright as possible or will any light do? Best bet is to just use the LCD backlight with an all white screen. You could leave the screen on in this way for over 20 hours.
3rd May 2014, 05:32 PM   |  #3  
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Originally Posted by bblzd

Do you need it to use the camera flash? In other words, does it need to be as bright as possible or will any light do? Best bet is to just use the LCD backlight with an all white screen. You could leave the screen on in this way for over 20 hours.

There's no way you're going to get 20 hours of screen on with an all white display

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3rd May 2014, 05:38 PM   |  #4  
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Quote:
Originally Posted by bblzd

Do you need it to use the camera flash? In other words, does it need to be as bright as possible or will any light do? Best bet is to just use the LCD backlight with an all white screen. You could leave the screen on in this way for over 20 hours.

lol, wont even be close to 20 hours.

and op, in order for you to use the led for a flashlight, even with the screen off, it will never go into deep sleep. it will be awake the whole time. in order for the device to run an app, a system or user app, you need the device awake. it will only go into deep sleep when nothing is active.
3rd May 2014, 05:51 PM   |  #5  
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Originally Posted by simms22

lol, wont even be close to 20 hours.

and op, in order for you to use the led for a flashlight, even with the screen off, it will never go into deep sleep. it will be awake the whole time. in order for the device to run an app, a system or user app, you need the device awake. it will only go into deep sleep when nothing is active.

I've seen it twice now, though I'm unable to find the links. One fellow on Reddit and another here on these forums. Both were well on their way to over 20 hours Screen on Time with little to no usage. Seeing as I've gotten over 8 myself with actual (albeit light) usage, it wasn't very shocking to see.

The screen with zero interaction uses very little battery due to Panel Self Refresh.
3rd May 2014, 06:00 PM   |  #6  
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Originally Posted by bblzd

I've seen it twice now, though I'm unable to find the links. One fellow on Reddit and another here on these forums. Both were well on their way to over 20 hours Screen on Time with little to no usage. Seeing as I've gotten over 8 myself with actual (albeit light) usage, it wasn't very shocking to see.

The screen with zero interaction uses very little battery due to Panel Self Refresh.

i still dont believe it. to get 20 hours, you would have to do more to your system than just turn on the screen. there are mods that reduce the brightness of the screen even lower than it normally goes, even to a point where its on, but you cant really tell that it is, its so dim. using that, maybe you can see 20 hours.
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