Android Device Manager Now Lets You Lock Your Phone Remotely
Google has added a new feature to the Android Device Manager recently. The Device Manager now lets users remotely lock their smartphones with a PIN code. If a smartphone is in airplane mode, it will be locked after it connects to Google servers again. To access the feature, go into the security settings and revert the password to the lock method that you want. Also make sure that the Android Device Manager is enabled in your Google settings app.
[Source: Android Police]