Mac ID allows you to open your Macbook/iMac using the TouchID sensor on your iPhone 5s/6/6+, or your passcode in iPhone 4s/5/5c. It also comes with handy features like turning your iPhone into a music remote control (just like Remote), it adds a widget to the Notification Center, and it comes in black and white (pink is the standard color) However, this nifty app comes with a price: $4 in the AppStore. Today, and for the next 48 (less at the time of this post), MacID is free.

Set up is easy, you just need to download the OS app through macid.co/get, install, and pair with your iPhone. However, there are 2 setbacks. Your Mac/iMac needs to have a Bluetooth LE profile and be on OS X 10.10 or higher, otherwise it won’t work.

You can see the full list of compatible devices here.