With AT&T and Verizon getting rid of their unlimited data plans for new contracts and Sprint not far behind, it will be up to you to make sure you don't go over your smartphone's data-usage allowance and get hit with expensive fees.
This week I have free apps for iPhone, Android and BlackBerry that will monitor your usage and help prevent any "sticker shock" on your next cellphone bill.
DataMan (iPhone), 3G Watchdog (Android) and Network Traffic Control (Blackberry) are all free apps for your smartphone. You can set thresholds for usage and then get warnings when you're getting close to exceeding them. You can also track data usage over time, and if you have an iPhone, DataMan can even geo-tag the stats to measure where you tend to use the most data.
In full disclosure, AT&T, Verizon and T-Mobile have their own apps for this as well, but they don't update as frequently as the ones mentioned, so it's possible that you could still go over your data limits before you even know it. If you don't have an unlimited data plan, fees can go up to $50 or more, so get an app and you won't get caught off guard!
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