Its phone upgrading season, and if you are looking to sell your phone on eBay or craigslist or friends or to any shops,Please dont forget to wipe your data before your phone changes hands. Heres a quick guide for anyone who might need it, so youre not fumbling through options and settings for half the day.

First, you should probably back up your phone using iTunes
Go to Settings
From there, go to General
Now go to Reset
Select Erase All Content and Settings
Youll be prompted to enter your passcode at this point
It will take a few minutes, unless youve got a fairly ancient iOS device
Android
Backing up for Android is relatively straightforward; just connect your phone to your computer via USB and drag all of your files into a new folder.
Pull down your Menu and go to Settings
Scroll to Privacy
Click Factory data reset
Windows Phone 7 and 7.5
Back up with Zune software if youre on Windows, but theres currently no way to totally back up your SMS texts for Windows Phone, so keep that in mind if you like to keep hang onto your messages.
Go to Settings
Tap About
Scroll to the bottom of the page and tap "reset your phone"
Press "yes" when the warning prompt appears
Warning: You wont be asked to confirm your password
BlackBerry OS 6
Use BlackBerry Desktop Manager to back up your phone
Go to Options
Scroll to Security
Now scroll to Security Wipe
Select all options (Email & Contacts, Applications, Media card)
Type the word "blackberry" into the box and hit confirm

Via : Gizmodo

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