The original S3 is a 3G-only device, but the Samsung Galaxy S3 LTE is an updated version with a new wireless chip to support 4G networks here in the UK. There are a couple of other tweaks too: the LTE phone has 2GB rather than 1GB RAM, and is available in a smart Titanium finish as well as the standard Galaxy S3 white. This 2GB version is currently upgradeable to Android 4.4. Samsung has officially ended support for the phone though, so you won’t be getting Android 5.0 by any official means.
The new handset has an identical chipset to the non-4G Galaxy S3, with its quad-core 1.4GHz processor, but has 2GB instead of 1GB RAM. We struggled to see what difference this made to the handset’s performance compared to a previous-model Galaxy S3 which we had upgraded to Android 4.1, and the handsets managed an identical 1, 771ms in the SunSpider JavaScript benchmark. Occasionally the 2GB handset would open and close apps slightly faster, but the extra RAM seems to make little practical difference in everyday use.
We did find, however, that the new version had slightly worse battery life than the old - we’re not sure whether this is due to the new operating system or the chipset, but in our continuous video playback test we saw 9h 19m from the Galaxy S3 LTE, compared to 9h 57m from the Galaxy S3.
If you’re picking up a handset second hand, you’ll probably find the battery won’t even last this long if the phone has had some serious long term use. It would be wise to pick up a replacement battery - it shouldn’t cost more than £20 online and it should have a longer lifespan than the one that originally came with the phone.