Awesome phone with attractive shape
I did a firmware upgrade on HTC desire 820s from kitkat to lollipop 5.0.2( sense 7.0) using the flash tools from xda developer site. Lollipop is slow and not optimized. I Recommend all the kitkat uses to use kitkat and not upgrade . Upgrade isn't worth it. RAM usage is too much .And battery drain is quicker. Trust me .don't upgrade
The phone is good while on its official software which is very good in performance
I recommend other people to buy but dont upgrade unofficially