How do I connect Notifyr?

First, you'll need to download the iOS application from the App Store. Then you need to download and install the Notifyr prefspanel for Mac.

Make sure bluetooth is enabled on both devices and open the iOS app. You'll be asked permission to your bluetooth settings and follow the instructions in the iOS app. As soon as you'll see an iPhone and animating circle 'beams' you need to go open the Notifyr prefspanel on the Mac. You'll find the prefspanel under the general settings panel from you Mac. Open the Notifyr panel and press the 'select device' button on the right bottom. While you Mac is searching for your iPhone make sure the iOS app is open to the foreground and you iPhone isn't locked.

Now you just need to select your iPhone on your Mac and enter the code to pair the devices.

Do not 'kill' (remove from multitasking) Notifyr. If you do, you'll need to reopen the iOS app to reconnect.

I don't have Bluetooth 4.0 on my Mac. Can I use a Bluetooth 4.0 USB dongle?

I haven't tested it but Thomas F. Starke was so kind to let me know that this Bluetooth dongle worked with Notifyr. If you succeeded using Notifyr with a Bluetooth dongle, please let me know if it works so I can make a list with supported dongles.