anybody knows which shop sells the genuine Samsung flip cover?

this flip cover is not the official Samsung one which I believe most people here are looking for.

Its a hard case right? won't it scratch the sides of the phone when you fit it in?

not sure if this is posted before, if you're noticing that your battery drains a little faster than it should be, most likely its kept awake by a process called "AudioOut_1". You can see this by using the app called "BetterBatteryStats".

To fix this issue, go to Settings > Sounds then uncheck "Touch Sounds" and "Screen lock sounds". After doing this, your phone should be able to go into deep sleep and you will get better battery life.

yes it can, with the app called 'Chainfire3D'

I was wondering why my phone feels a little laggy till I finally found out that Power Saving option was on. It actually limits the CPU performance and reduces the screen frame rate. And it doesn't save battery that much also.

From my experiences with hard cases, they will definitely scratch the sides of the phone. So be careful in which case you choose to put on your phone. Unless you gonna put it and leave it on forever.