So glad to have found that app! I had bought Domain Tracker in 2004: it was discontinued. Then I bought Domainer: it did the job properly for several years, but was discontinued last year as well. Finally, I have now found Master of My Domain. After those previous experiences, I approached it cautiously. But I was impressed: when I submitted a pre-order inquiry mentioning a bug, not only did I receive a personal and precise answer within a few hours, but also an updated version fixing the bug!
What is still missing at this point are domain groups within the app: but the developer has kindly informed me that this feature would soon come with the next version, i.e. 2.1.
Moreover, the app is more powerful and offer more features than its discontinued competitors used to. Not only does it allow to list domain names, but also a variety of information related to each domain name: FTP information, email addresses with user and password, logins, subdomains, databases with all details...
I first regretted having to give up the previous app, but discovering Master of My Domain now makes me think that it is actually a blessing of disguise to need to change.
The only thing that I am not yet able to assess is the stability of the app with several hundreds or thousands domain names: not enough time spent using it, and I wait until domain groups are available in order to import most of my domain names.
Finally, the best for the end of this short review: the developer has assured me that the app "will continue to be updated and supported". With the vanishing competition, definitely the best option left for Mac users who need to manage domain names.
( I had also a pleasant surprise when buying the app: currrently, the store of Apple Source Software offers it at a discounted price of $20.)