On Android, open the Google Play app, tap the More settings button (the three dots in the upper right-hand corner), then select Settings from the menu that appears. Next, tap Auto-update apps and then select Auto-update over Wi-Fi only.
Yes, you really can make a 2GB data plan work
You will have to sacrifice some convenience to stay within your data plan's limits, but it's definitely worth the effort. Plus, do you really need to see every "like" your latest Instagram post gets--as soon as it happens? Probably not. Just remember to disable all of the stealthy data hogs described above, and download everything you can--whether it's an app, an email message, or a website--over Wi-Fi. If you can do that, stretching your data plan will be a cinch.
[This is an updated version of a story originally published on Sep 5, 2013.]
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