While on holiday this week, I discovered a need for a Roaming Manager app that doesn't seem to exist. I bought a bundle of roaming data, to enable me to view emails, update Twitter, use Google Maps etc. But it's hard to restrict data to certain apps - for example, Market still phones home (and downloads anything set to update automatically) and Lookout still wants to backup unless you remember to turn it off. What I'd really like is an app to allow roaming data access to only certain apps. So, you set "Allow Roaming" through Android settings, but the app would detect that you're roaming and only allow data access to selected applications, say GMail, Maps or Browser. Is this possible to build and does anyone fancy doing it?