This is absolutely yet another LATE POST. Just for my reference and/or to help those that are facing these issues.
My Samsung S3 (9th handphone) started having some issues around 1.5 to 2 years ago (perhaps circa mid year of 2016). Actually few months after I blogged about this handphone, it started lagging noticeably, but I hold on to it. I gotta make my money worth!
Ok, so the issues I had with my Samsung S3:
1. Battery draining very fast. I suspected this was due to an app that I downloaded. It was so bad that I had to reset the phone to factory setting few times. Battery life improved a bit but I still need to charge the phone almost twice daily. I even bought a new battery, but no help there.