TinyTERM for Mac is licensed with a 25-character alphanumeric activation key. When you first start TinyTERM, or when the evaluation license has expired, a warning message will come up that says TinyTERM is not licensed:

If you do not have a key, click the Get License button on this dialog. If you prefer, you can also visit our purchase page or contact our sales department to purchase a license.

To enter a key, click the Enter License button to bring up the "Add License Key" dialog:

Copy and paste the Registered To: name and Activation Key: into the appropriate lines. The Add Key button will become available. If it does not, check the name and key for typos. Note that if your license did not inclued a Registered To: name, then the name isn't required for licensing TinyTERM.

After clicking Add Key, TinyTERM will start. You will not need to add the key again.