Having just come back from a couple week excursion abroad, I wanted to share my successes with managing the roaming data battle.
Optimizing your data connection for roaming is in a nutshell really all about:

• Preparing before you go
• Optimizing your connections – I found that surgical strikes work best, that is, know what you need to do, go online and getting it done, then go offline.
• And this is going to hurt but you are not going to want to use *any* photo, video or streaming music apps unless they support offline caching

Before you go:
Buy an AT&T plan

• I use AT&T and they have a product called AT&T Passport (login required) that gives you a certain amount of roaming data. You definitely don’t want to go over your limit, so the key then becomes optimizing for data hungry devices. You also get discounts on phone calls, and international SMS

Optimizing your App Connectivity

• Go to Settings > Cellular ( you will need a cell network connection to do this, so do it while at the airport waiting for your outbound flight)
• Scroll down to the section “Use Cellular Data For:” and turn OFF every app that you don’t see needing or wanting to use. I just turned everything off to start.
• Then as you go to use your device and select an App, if it requires Internet access, you will see a dialog telling you to turn on the cellular data for that app. The benefit is that there is no background data used but any app.

While You’re Abroad:
Using apps is simple:

• Keep Data Roaming turned off at all times until you’re ready for a surgical strike
• Turn on data roaming
• Turn on cellular data for your app
• Do what you need to do, quickly, and don’t get sucked into random online activity
• When you’re done, you can optionally turn off cellular data for that app
• Then turn off Data Roaming

Realtime Data Monitoring

• Reset your cell data on your outbound flight over
• Get yourself a data monitoring app with a Today screen widget and usage based notifications, and optionally an Apple Watch view. There are a bunch of them and they’re all fairly similar but I use Dataman Pro

Google Maps:

• I love Waze for driving but Google Maps is great abroad because you can put in a destination, get walking directions, and then turn off data. Google Maps is smart enough to leverage the GPS connection which is free, so it auto updates.
• You can also cue up some offline maps if you know you’re going to be in an area ahead of time

Music:

• All the services have download options if you happen to be a premium subscriber. I’d seriously argue that it’s insane to not be paying $10/month for music (that’s 1.5 beers or 2 Starbucks lattes for goodness sake), but if you don’t, go ahead and subscribe for the time you’re away.  (Note that I work at Rdio fwiw)
• Go and download and most importantly sync your music. there’s no real limitation to how much you can keep local except for the space available on your device. I have 40GB of music on my iPhone

Video:

• You can go and buy content on iTunes and download to your device
• I happen to love oPlayer (iOS). It allows you to sync local content via iTunes and plays back almost all file formats.
• Local content will help keep your bandwidth and sanity in check during inevitable travel delays or long flights/train ride.

Email:

• Turn off images in email if you haven’t already done this. I keep mine off always by default, but this will save you precious MBs
• Batch them when you’re in wi-fi enabled places, like airports, train stations, cafés and hotels

Wi-fi

• This is a no brainer, but find wi-fi in places you’re going to be and batch your big online tasks like retrieving all your email
• Please get yourself a VPN – I use Cloak (iOS and OS X only for now) for its simplicity of install and use, and automatic enabling on untrusted networks.

News:

• I can’t recommend this combo enough: Feedly Pro > Newsify. I will document this is a separate post shortly

When You get Back:
Feel free to re-enable all your apps in the Use Data For section and breathe a sigh of relief that you don’t have a many thousands of dollars bill coming your way.
Let me know what you think on Twitter – I’m @sp