When it comes to my device I can be pretty careless. I'm constantly losing it at home or misplacing it at work. Normally there's nothing on there that would come back to haunt me as I'm a pretty boring person. However, my BBM's are a different story. That's where Lock BlackBerry Messenger by Ajani InfoTech comes into play. It keeps your BBM messages secure without locking the rest of your device down. This way you still have access to other applications such as such as your phone, internet, apps, and email.
This is a pretty good app when it comes to your personal privacy and security. Plus it's very easy to use. Simply enter in your new password and choose whether to enable / disable the lock. Anytime you click on your BBM icon or access via the app switcher you're prompted to enter in your password. It even pops up when entering and exiting BBM Groups which in my case is a good thing.
I did notice that it does not prevent BBM access from the messages application and doesn't time out if you're chatting and put your device down. These little hiccups aside if you would like to keep your BBM's hidden from unwanted eyes then this is the app for you.
Lock BlackBerry Messenger: Password Protect BlackBerry Messenger is available for $1.99 for all devices running OS 4.2 and higher. For a limited time it's on sale for $0.99. You can't go wrong with that.