Unlock your Mac with just your fingerprint, passcode, or wrist – without even unlocking your iOS device.
MacID requires a Mac with Bluetooth LE (Low Energy) running OS X Yosemite or later, and an iOS device with Bluetooth LE running iOS 8 or later. Please make sure your devices support Bluetooth LE before purchasing MacID for iOS.
• MacID works with multiple Macs at once.
• Unlock your Mac using Touch ID, device passcode, and now your wrist with MacID for Apple Watch!
• Apple Watch Glance for super quick access.
• Interactive notifications – you don’t even have to unlock your iOS device.
• Control your Mac’s audio; works
Read more here: MacID for iOS and Apple Watch – Kane Cheshire