iOS Activation lock does its job and discourages thieves - statistics show a massive drop in stolen iPhones12
So far, Apple's iCloud Activation Lock is the most straightforward of said solutions – it goes on automatically, once the user switches the "Find my iPhone" function on, and will stay ever-present, turning the iPhone into a fancy paperweight, if a person who does not know your iCloud user name and password tries to deactivate "Find my iPhone", or wipes the handset. Buyers of second-hand iDevices can also visit the iCloud website to check if a handset they are eyeing is locked.
The Lock's popularity has obviously caught on, as a year-over-year statistic shows that iPhone theft has dropped by 40% in San Francisco and 25% is New York, while officials across the pond claim a 50% drop in stolen smartphones (it is unclear, whether this covers all smartphones, or just iPhones).
Come July the 1st, we will probably be seeing a lot more activation locks on all kinds of handsets. Android has the remote Device Manager, which can be accessed at www.google.com/android/devicemanager, but the tool requires the phone to still be both connected to the Internet and to your Google account for it to work, which gives thieves a lot of leeway. Windows Phone 8.1 still lacks such a feature, though, Microsoft has said that it will be present in Windows 10.