I have been using my Nexus 7 2013 for few months and the battery is really strange.
The battery graph is often zigzag-like as attached and I really don't know where the issue is.
I have been using purity rom, franco kernel with smart cover.
I am also charging my Nexus 7 2013 with my Nexus 4 charger and external powerbank.
Is this a battery problem and should I get it back to ASUS for warranty?