New answers tagged dialer
According to the screenshot, the app is not requesting any special permissions. If your phone is not rooted I'd say: Its safe.
Proximity Fix app helped me on Samsung Galaxy Note 2 and in the reviews, fixed it for Nexus 4 as well. Maybe it is worth a try? EDIT: Disable Proximity Sensor AOSP thread may give a pointer on disabling proximity sensor by echo command.
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