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Protect your data while traveling
Learn how to protect your smartphone and its precious data.
Tips for selling an used phone
So, you want to sell your old smartphone. That's a great idea, but you should make sure that you aren't also passing your private data, photos, etc. to another person. Here's how to clean up your device before selling it.
1. Remove the SIM card.
If you have purchased a new phone, chances are that you've also gotten a new, tinier SIM card with it. However, the old SIM has stored the names of your contacts on it, so you'll want to keep it for yourself or destroy it, in case that you've got no use for it.
2. Remove the SD card.
Android phones can make use of memory cards, and most apps save data (including pictures, movies, etc.) on these cards. Therefore, you shouldn't sell your phone before removing its SD card. Actually, since most Android-based phones can make use of Secure Digital cards, you can easily reuse it, plugging it into your new phone.
Some people choose to format the memory cards before selling their phones, but there are lots of apps which can restore all the data that was stored on those cards within minutes. There is a simple explanation for this: to save time, whenever you delete a file from the phone's storage, the file I/O system doesn't take the time to zero all its bits; instead, it marks the storage space that it is used by that particular file as being "free" in the file allocation database, allowing it to be overwritten with fresh information. Data restoring apps look for contiguous chunks of data, and then will effortlessly recreate the deleted files.
So, if you really need to sell your memory card together with the phone, remove it, connect it to a compatible adapter which can be plugged into your PC or laptop, and then install a military-grade data deletion application and run it. Once that the secure data deletion process has finished, reinsert the properly formatted card into the old phone.
A much faster, but not 100% safe alternative is to encrypt the data on your SD card using a very strong password, and then format it. Use this method only if you don't own a personal computer, though; the scrambled data still can be unmasked, and its integrity will only be protected by the complexity of the chosen password.
3. Erase the phone data.
It goes without saying that you should back up any useful data you've got on the phone first! Then, it's time to sign out of your Google account, and then delete, remove and/or uninstall the account settings, apps, music, photos, etc. Don't forget to sign out of accounts, and then uninstall the social media apps as well.
4. Reset the phone.
It's time to reset the phone to its factory settings. The process should only take a few minutes if you have removed the SD card, or several hours for people who have stored a lot of data on their memory cards.
To get a good deal, be sure to clean the phone thoroughly. Take great photos of your phone, and then post them online; use a friend's camera, if yours is outdated. Include as many of the original accessories as possible.
There are several other things that you can do with an old phone besides selling it, of course. Here are a few ideas:
- Gift it to a person in need;
- Donate it to a charity;
- Trade it in and get a discount if you plan to purchase a new phone.
