Cut back on other data-heavy apps, too
You now know that it's best to keep Netflix and Pandora mobile marathons to a minimum, but don't forget about other data-sucking apps. Social networking apps (which are constantly updating in the background), games (which push ads and notifications to you), and cloud-storage apps such as Dropbox or Google Drive (which constantly download files to stay synced) can drain data without your knowledge.
You need a tattletale app, one that reports on how much data each app on your phone is using. We recommend downloading a third-party app such as Onavo Count, which is available for both Android and iOS. The free Onavo Count shows you how much data your apps are using, but it doesn't stop there--you can generate weekly and monthly data usage reports, as well as an app guide that shows a list of the 20 most popular apps and how much data they use on average.
Onavo Count also has a "You vs. Everyone" analysis feature, which tells you how much data each of your apps is using in comparison with other people's apps. This function is helpful because it can alert you to excessive data usage; for example, if your Dropbox app is using way more data than other people's Dropbox apps are, you should probably tweak your sync settings and rein in your mobile Dropbox use to reduce data consumption.
Another way to cut back on data-heavy apps is to use "lightweight" apps for everyday tasks, such as Web browsing. For example, Opera Mini (Android and iOS) is a lightweight browser that compresses websites before sending them to your device. If you don't mind text-only browsing, TextOnly (Android) and Text Browser (iOS) are extremely lightweight browsers--they show only the readable text on a webpage. You'll save data, since you won't have to worry about downloading large graphics, photos, or ads.
Turn off background app refresh
Both iOS and Android allow apps to use your cellular connection to pull in data while in the background. For example, an email app can fetch new messages, a photo app could upload or download the latest pictures you've taken, and so on.
To disable this feature on iOS, open the Settings app, tap General, then tap Background App Refresh. Next, switch the Background App Refresh to its off position--it'll switch from green to white.
On Android, open the Settings app, tap Data Usage, then tap the More Settings button in the upper right corner (represented by three dots). Next, check the box labelled Restrict background data. Android will ask you to confirm; tap OK to do so. If you connect to a Wi-Fi network, apps will be able to use that to send and receive data in the background, so it's not an all-or-nothing setting like it is on iOS.
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