Do I have to purchase multiple licenses in order to run AirBuddy on multiple Macs?

You don’t. A single license gives you the right to run AirBuddy in up to 5 Macs. If you’re trying to activate the app but there’s an error with the activation, that might be because you’ve exceeded the number of allowed activations per license.

You can get an extension to your activation limit by emailing your license key to [email protected].