I have zenfone 3 5.2inch version. I like this phone very much, solid build and solid battery life for me. However, there is a problem that I've noticed since i bought it. The camera have flickering issue. I know the stock camera apps have no problem, since it can adjust the frequency, but the problem comes when using third party apps like whatsapp, insta and so on... And the issue appeared during nighttime when lights on. I know it is a power source issue, but anyone have any solutions for it?

a) What is the average SOT of ZE520KL? Battery only 2650mAH
Well, I manage to get 5 to 6 hours solid with medium usage, mainly youtube and facebook
b) Does it have dual app for Whatsapp, etc?
I didnt try before, I think it dont have that function.
c) Have anyone tried & able to use those SIM/MicroSd extender so that we can use all both sims together with microsd?
Havent try before also.