If an Android device (phone or tablet) has ever logged on to a particular Wi-Fi network, then Google probably knows the Wi-Fi password. Considering how many Android devices there are, it is likely that Google can access most Wi-Fi passwords worldwide.
Some back-of-the-envelope math points us to the estimate that 748 million Android phones will ship this year. That's phones alone – Android tablets add to that figure.
With this many of its own devices in the wild, it becomes easy to see that Google has access to all order of Wi-Fi passwords.
This is all possible because of a feature that lets you back up and save your data to Google's servers. This includes the obvious, like backing up your phone book and calendar, but it also snags your Wi-Fi passwords in the process. The feature is presented as a good thing, and by and large it is – if you lose a phone and need to replace it, all your data is backed up thanks to Google. No obnoxious re-entering of all your friends' and family's phone numbers, no need to scrounge up the passwords for your various Wi-Fi networks.
If the privacy implications of this outweigh the convenience, you can opt out by unchecking the appropriate box in your settings. Horowitz offers the following instructions on how to navigate to the appropriate dialogue:
- In Android 2.3.4, go to Settings, then Privacy. On an HTC device, the option that gives Google your Wi-Fi password is "Back up my settings". On a Samsung device, the option is called "Back up my data". The only description is "Back up current settings and application data". No mention is made of Wi-Fi passwords.
- In Android 4.2, go to Settings, then "Backup and reset". The option is called "Back up my data". The description says "Back up application data, Wi-Fi passwords, and other settings to Google servers".
It's also worth noting that like all personal data stored in Google, humans aren't looking at your Wi-Fi passwords. This tool is simply a convenient feature for Android users who don't want to keep re-entering their passwords.
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