What to do with your old Android phone before selling it

[johnypowas]

iOS
Lexy Savvides/CNET
Apple devices that support iOS 5 or later include hardware encryption when you set a passcode. If you perform a wipe using the method below, the encryption key is also overwritten, which makes it very difficult for anyone who wants to recover the data.
Step 1: Before starting the reset process, make sure to unpair devices like the Apple Watch($409 at Walmart). Then, turn off Find My iPhone ($599 at Amazon). For iOS 10.2 or earlier, go to Settings > iCloud > Find My iPhone. Enter your Apple ID password if prompted. For iOS 10.3 or later, go to Settings > Your name > iCloud > Find My iPhone.
Step 2: Turn off and sign out of other services including iMessage and the App Store. Go to Settings > Messages > toggle the iMessage option. For your Apple ID, go to Settings > iTunes & App Store > tap your Apple ID email address and then tap Sign Out.
For added peace of mind you may also want to sign out individually from any other linked services and apps, such as Facebook or Twitter.
Step 3: Sign out of iCloud completely. Head to Settings > iCloud and find Sign Out at the bottom of the page. For iOS 10.3 and later, Settings > Your name > Sign Out. For iOS 7 devices, choose Delete Account.
Note: if you delete all your data manually without signing out of iCloud, it will also delete the content from iCloud as well -- which is something you definitely don't want.
Step 4: Start the wipe process. Go to Settings > General > Reset > Erase All Content and Settings. Confirm the selection.
Step 5: Remove the serial number of the device from your Apple account profile at appleid.apple.com.