They sell local SIM cards so it varies from country to country. One of the  USA plans , from what I know, gives you 5gb of 4g data 

I have friends who have used the USA SIM card from simcorner. They couldn't have been happier with the service and quality. I personally have been looking at simcards as well and have done extensive research, travellers should be weary of sites charging for blank simcards with no credit in them. ...