There are several apps available on Play Store for password protecting individual apps on Android phone. Lockdown Pro (it is completely free, no ads) is a new, app locker for Android that offers some excellent features to lock and unlock apps.
You can choose PIN or Pattern lock to lock/unlock applications. It offers three password modes – Pattern Lock, Classic Lock and Calculator Lock – to choose. Besides the password lock, you can set pre-defined locations to auto lock/unlock apps when you get in/out your setting locations. Another interesting feature of this app is that you can simulate an application force close. It will prevent users from knowing that they were intentionally locked out. What’s more, it is easy to use and the interface looks so beautiful. The setup and lock screen looks cool and clean. Also, so many beautiful themes are available for your choice. If you are interested, head over to Play Store to get started. (source)
