I understand it, although I think it's quite colloquial. "Use my phone" would imply using it as a phone for making calls/texts etc., "going on my phone" sounds to me like using my phone for playing games or browsing the internet - generally to waste time.

Hi! Yes, if you hear an English speaker say, "go on my phone", "I'm going to go on my phone and check..." "I'm going to go on my phone and look..." that basically means, "I'm going to use my phone." So you can say, "On the weekends, I like to lie in bed and read or go on my phone." :) Best, Jillian

Helen, Yes, "going on my phone" is another way of saying "using my phone". Yes, you can replace it with that phrase, but in this particular sentence it will have to be "using my phone".