Selling Your Old Phone: What You Need to Know

So the fancy new phone-of-the-moment has just been released – the iPhone Nexus 9xs or some such – and you’ve got the itch, eh? Or maybe it’s just time for an upgrade. Either way, selling your old phone is an easy way to offset some of the cost of the new one but it is not without risks. Just think of all of the stuff on your phone: pictures (all SFW, right?), videos, call logs, logins for websites (you didn’t log in to your bank account from your phone, did you?), text messages, and more. I’m sure you would not like the new owner of your phone to be able to access some of these things. Deleting this data can be complicated as phones are not just like computers, they use different operating systems, different techniques for data storage, and you as the owner don’t normally even have administrator (or root) privileges on your device. Also keep in mind that there are tools for recovering the things you think you’ve deleted long ago. With that said, don’t despair! Read on to find out how to ensure that your private data stays private.

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Luckily the process of readying your phone for sale is not difficult if you just follow some basic steps. Although creating a backup and wiping data are a bit different for iPhone versus Android-based devices, the general process looks like this:

  • Backup your current settings and data
  • Remove extra data cards like your SIM card and SD cards
  • Wipe the device clean (destroy the data) so that none of your stuff is recoverable
  • Notify your carrier that the phone is no longer yours
  • Profit (safely)!

See the appropriate section below for specifics depending on whether you are selling an iPhone or an Android phone.

iPhone Specific Advice

For backing up an iPhone, you have two options: you can use iTunes to back up your data to another computer or, if you have access, use iCloud. Either of these methods can help you move your data and settings from your old phone to your new one. Look here for details from Apple.

Wiping an iPhone so the data is unrecoverable is about as easy as it gets. Just navigate to Settings > General > Reset > Erase all Content and Settings. On older models (before iPhone 3GS and iOS 3.0), this will overwrite the all of your data on the device. This process can take a considerable amount of time – sometimes on the order of hours – so be prepared. On newer models, the device storage is encrypted by default at the hardware level. In this case, only the encryption key is destroyed. While this may seem too simple, destroying the encryption key effectively renders the data on the device unrecoverable. Thankfully, it’s also almost instantaneous. One thing to be careful of: if you are using iCloud, make sure you do not manually delete contacts, photos, etc. on the phone as these deletions will be propagated to the iCloud servers. (Clearly this does not happen when you “Erase all Content and Settings” as specified above.)

Android Specific Advice

Android phones are available from many manufacturers and carriers, with different versions of the Android OS, which makes the process of backing up and restoring more complicated, but here goes. First, if you already have a Google account associated with the device (via Settings->Backup and reset), then things like text messages, contacts, calendar, mail, and some system settings are already taken care of as they are synced to Google servers. Other types of data, like pictures, videos, and application specific data are more difficult to deal with. These will generally require 3rd party apps to back up. Be aware that some backup apps are free while others are not and that some only work on rooted devices (if you don’t know what this means, assume you’re device is not rooted).

For the same reasons listed above, wiping an android phone is also somewhat complicated. Android systems do not generally encrypt data by default, so just wiping the encryption key is not an option. There is usually a Factory data reset feature in Settings->Backup, but depending on many factors, it may not really remove all of you data. The best course of action is, again, to look to 3rd party applications to wipe all of your data and then do a Factory data reset.

I hope this provides some valuable information on how to keep your data safe when selling your old phone. Now go out and get that iPhone Nexus 9xs!


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