The Database Tour (Pro) is shareware with 24 day trial period. During the trial period, you may use it without any limitations. After the trial period, it must be registered for further legal use. If you don't want to register Database Tour (Pro), it must be removed from your computer immediately after the trial period ends.
To register the application, you must purchase one or more Database Tour (Pro) licenses.
If you have Internet connection on the computer, where you use Database Tour (Pro), you can purchase it directly from the application by choosing Help | Buy/Register... | Register.
If you don't have Internet connection on the computer, where you use Database Tour (Pro), you can purchase it using browser on another computer which has the Internet connection. This can be done on Database Tour web site, Ordering page:
On this page, you can also find the information about current prices, discounts, and purchase and registration instructions.
The answers on some purchase and post-purchase questions can be found in Database Tour FAQ: