[leeleelee]

I have the S3 and I can't wait to upgrade. It is SLOW (noticeable lag). Plus, not sure what causes this (hardware or software) -- but the GPS navigation is terrible. I'm stuck on Android 4.4.2. Takes forever to lock in on my location, loses signal randomly, and sometimes in the middle of navigation it stop updating where I am on the visual display. The camera is horrendous. So, speak for yourself. Phones have come a long way since the S3.

[galvan]

Random digression, but if you're having problems with GPS reception on your S3, try tightening all the screws on the back of the device with an eyeglasses screwdriver or similar. The GPS antenna(e) are in the screwed-on backplate and connected via sprung contacts to the mainboard, so if the screws aren't tight, it won't make a solid connection. You can also try removing the backplate and (gently) prying up the spring contacts at the bottom of the motherboard, and then cleaning both them and the contacts on the backplate with isopropyl alcohol. I bought my S3 used and couldn't get a single GPS fix, but after tightening the (noticeably loose) screws, it now happens in a few seconds.

[ikeboy]

You can use lollipop if you're willing to install cyanogenmod. There are also marshmallow builds, depends on which variant you have.

[gkoz]

AFAIK there's no way to unlock the bootloader of the Verizon variant once upgraded over the air to 4.3 or later.