Since TNW2011 I have traveled to Spain and Germany so I had a good opportunity to test the app. For those who don’t know what Onavo is: it is an iPhone app that compresses your data and saves you up to 90% on your data roaming costs.

Halfway Onavo’s presentation at our conference I stopped listening and installed the App. Their proposition was almost too good to be true and I knew I wanted it. The app is (currently) free and can save you hundreds of euros or dollars in roaming fees. Who doesn’t want that?

screenshot My trip abroad with data cost saving app OnavoSince then I have been able to put the app to practice and found out some interesting things. As you can see in the screenshot on the right Onavo saved me 5.58mb or 39% on my most recent trip.

That doesn’t seem like much until you realize that I’m paying €1.68 per Megabyte in Germany according to T-Mobile. That means that I saved €9.4 in roaming cost, on just this trip.

This month I also visited Spain for a week where Onavo saved me €121. That was a different story though.

While waiting for my plane in Amsterdam I launched the appstore and updated some apps. One seemed to take a while.

In fact, when I boarded the plane the app still hadn’t downloaded and then I switched off the iPhone and forgot about it.

As soon as I landed the app started downloading again in the background, over 3G, in Spain. Sigh.

Fortunately for me Onavo compressed that data too and saved me a lot of money.

Another interesting thing to look at is how Onavo compresses data. As you can see it does very well with web browsing where it compresses as much as 77%. Results may vary with other apps. MobileMe isn’t compressed at all and Apple GPS seems to use data too.

Apparently I also checked Onavo’s status a few time this last trip which cost me 198 kilobytes and which Onavo doesn’t compress. Weird.

All in all I can recommend installing the app, if you have an iPhone and travel and want to save money. Right now it is free, easy to set up and will start saving you money right away.

Martin had a chance to interview the Onavo founders at TNW2011: