Blink notifies you whenever any of your Macs wake or sleep, so you can stop intruders in their tracks. You never have to open the app a second time - just carry on with your normal routine and your Mac will send you notifications as needed.
Odds are that you leave your computer alone somewhere everyday, leaving it vulnerable to anyone trying to guess your password. But hey! You always have your iPhone/iPad/Apple Watch with you, and with you. With Blink running, you'll never have to worry again.
Blink was created at Europe's largest hackathon (programming competition) in Zürich, Switzerland.