For those of you who have been waiting for a Android 5.0.2 Lollipop ROM, there’s been many beta versions in the last few months.
If you own the GT-i9300 model, you are in luck as the Lollipop ROM runs near flawless with everything working out of the box. As for AT&T, T-Mobile, Sprint, or Verizon S3 users, you will also get pretty stable build except the camera/camcorder is not working. (You can get still photos working sorta with Open Camera app.) If this is a concern to you, you may want to wait out few more weeks for camera fix.
For running the latest Android 5.0.2 Lollipo ROM, I do recommend CM12 ROM for all Galaxy S3 models for now as you will get the latest updates/fixes as other AOSP ROMs are built on top of CM12’s source code.
Again, for GT-i9300, CM12 is near flawless and I highly recommend the Temasek builds. As for other S3 models, you will have to try the beta CM12 ROMs, which are pretty solid except the camera.
Overall, it’s been a very slow progress for the Galaxy S3 but we should have fully-working Lollipop ROMs soon for all of you without GT-i9300. In the meanwhile, go knock yourself out with these CM12 ROMs. At the worst, you can go ahead and make a backup ROM, try the Lollipop ROM, then revert back to your old ROM.
Download Android 5.0 Gapps (use standard)
To install, reboot into recovery, make backup ROM, format /system, wipe data/factory reset, install ROM, install Gapps, and reboot.
First time installing a custom ROM? See How to Install Custom ROM on Galaxy S3!