Buyers of used equipment are often concerned about purchasing hot goods. Moral questions aside, when it comes to iPhones you want to be certain that the device isn’t Activation Locked—this prevents it from being used until it’s unlocked with the rightful owner’s Apple ID credentials. Apple now provides an iCloud portal where you can you enter a device’s serial number or IMEI to check its lock status.
You’ll have to use a desktop browser, Mobile Safari won’t work. At this time the tool is targeted at desktop browsers. If you want to access the site using Mobile Safari (iOS 8) you’ll need to jump through extra hoops:
Go to icloud.com and use the Request Desktop Site feature:
To access this, give a gentle pull down on the menubar to see two new choices: Add to Favorites and Request Desktop Site. Tap the latter and the page will reformat, usually presenting itself in desktop glory.
Once you’re viewing the desktop version, type icloud.com/activationlock into the URL bar.