I don't have a G2 but I absolutely love the knock-on feature which has been brought to other devices using custom kernels. On my device at least (Nexus 5) enabling this feature entails a significant battery drain.
My question for you G2 owners is: are you able to disable the feature on your phone, and if so, is there any effect on your battery life, i.e. is it better without knock on?
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