There is strange bug with navigation bar. Sometimes it just stop working and I have no idea why this happens. Reboot solves this problem.
It's not the navigation bar issue, its issue of bottom 1.5cm part of the touchscreen, which is unresponsive. You can fix this without restart, go to Settings -> System -> About phone. It will load the info about the touchscreen, and it will fix it, but just for a while. Next day it will be the same.
Do u get any stopped working notification as it happens generally when app hangs. Is the notification panel accessible when happens this.
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