Basic good manners seem to a thing of the past. It is very rude to ignore the person you are with and divert your attention somewhere else, especially as you had been asked not to.
This exactly. The fact that many posters on this thread are defending the rude and ignorant behaviour of the OP shows how rude and ignorant and obnoxious and entitled society is becoming.
CLEARLY they would think nothing of fucking about on their phone (whilst in the company of someone else,) even though they could have waited til later.
The OP's partner asked her to stop looking at her phone, and she ignored him and carried on looking. So I don't blame him for getting up and walking off. I bloody would too. Totally ignorant and rude behaviour from the OP.
If the shoe had been on the other foot, and it had been the OP who had walked away, (because her partner was rude enough to start messing around on the internet on his phone when they were having a meal together,) these same people (defending her here,) would be saying 'good for you! How DARE he start messing about on his phone when he is with you?' LTB now!!!'
Typical double standards that I see on here all the time.
@Bluntness100
this is victim blaming at its worst.
FFS, just when I thought I had seen it all. Don't talk such utter dross! Dramatic much? 
If this man is so pathetic, and such a monster, then the OP is quite free to not see him again. I'm sure he will get over it. 