Keep certain apps off of cellular data
iOS 7 lets you keep certain apps from using your cellular data connection, forcing them to use Wi-Fi. This could be especially useful if you have some apps that are particularly data-hungry.
Pop open the Settings app, then tap Cellular. Here, under Use Cellular Network Data For:, you can see how much you've consumed--but only since the last time you reset the tracker. If you don't reset the tracker at the beginning of each new billing cycle, this statistic is useless.
You'll also notice a toggle switch next to each app's name. If you want to keep any of these apps from using your data plan, slide the toggle to the off position.
Use Wi-Fi whenever possible
If you have regular access to a Wi-Fi network at home or at work, use that instead of your cellular data connection: When you connect to Wi-Fi, apps will use that for uploads and downloads, thus sparing you from going over your data cap. The downside? Using Wi-Fi may drain your battery a little more quickly.
Trying to find a good Wi-Fi network can be tedious, so use a free Wi-Fi finding app, such as JiWire's Wi-Fi Finder. Available for both Android and iOS, Wi-Fi Finder contains a database of over 550,000 Wi-Fi hotspots in 144 countries. You can use the app's regularly updated hotspots map in conjunction with your phone's GPS function to find the best Wi-Fi in your area, or you can download JiWire's database so that you can still peruse its map of Wi-Fi hotspots even if you're currently offline.
For every hotspot, Wi-Fi Finder lists details that you can't get from your phone's settings menu, such as the provider (AT&T, Comcast, or the like), the type of location (hotel, café, and so on), and whether it's a free or paid hotspot.
Avoid streaming music or video on the go
It may seem obvious that streaming audio would eat up your data allotment, but it can eat it up more quickly than you might think. So limit the amount of time you spend streaming Pandora or Netflix while on the bus.
If listening to podcasts while commuting are your thing, consider downloading the episodes you want to listen to using your home Wi-Fi connection before you leave in the morning. The same goes with music: Transfer a playlist from your iTunes library to your iPhone so you don't have to stream it later.
At the very least, see if the app you're using to stream audio gives you the option to adjust the audio quality (bitrate). If you can adjust it--and if you can tolerate lower-quality audio--that's another way to limit the strain you put on your data plan.
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