Nexus7 use in London
 

Greetings,

We will be staying in London for the month of September,2014. I'll want to use my Nexus 7 for navigation around town using a map application,for email and browsing.I'm going to try to use Skype for the occasional phone call to a restaurant, site or our B+B.
The Nexus7(2013) is unlocked with 4G.
Would you make a recommendation for a payg service that would do these things well and economically .

Thanks very much for your suggestions.