I’ve found two ways to prevent this from happening:
Save up to 80% bandwidth
The Onavo Extend app uses Onavo servers to compress data before sending it to your phone. In the short time I’ve had it, it cut 70% of my web browsing bandwidth. Overall, it cut data usage by about 49%. The overall savings is lower because Onavo can’t compress video like it can compress images.
Great for travel
Saving a couple of megabytes may seem trivial, but it adds up – especially when you’re traveling. Mobile operators sometimes charge expensive roaming fees or even charge per megabyte.
(Tip: If you’re traveling internationally, unlock your phone and just buy a new sim card. You don’t want to pay international roaming.)
Customize what you save
Onavo lets you choose how much to compress images, so you don’t have to worry about looking at crappy images.
If you don’t ever get close to your data limit, you don’t have to bother with this app.
But if you do, Onavo is invaluable.