I am using samsung tab 3 SM-T311 But i cannot find right frimware for it. Updato app says that 7.0 is latest but when i search on website it says 4.4.2 is latest. Which one is correct?
Unfortunately, all we feature is what Samsung releases - it's possible that Samsung hasn't released any newer firmware.
Can get a costom rom for 6.0 android?(with the model - SM-T311)
You can achieve that but only with custom ROMs, like this: https://www.youtube.com/watch?v=rCOZ4MI2x14