Lock App enables you to lock/unlock your mac remotely using your phone automatically. Now you dont have to do anything just approach your Mac with your iPhone in your pocket to unlock your Mac. And walk away to lock it up. All this is possible without the need to open any app on either your phone or Mac.
Please download and run this on your Mac after you install the iOS app:
http://jog-a-lot.com/LockAppBT.dmg
Demo video:
http://youtu.be/YDG8Bt_iNkY
Follow the instructions in the video to set up your Mac with your iOS device.