It was a very interesting topic, so I finished it quickly. The explanation was also neat and clear. (However, it might be a little difficult for those who are new to the web.) If I were a little greedy, I wish it was a more detailed clone? lecture, as you are the developer of the original Corona map. For example, if the lecture included a database for managing markers or a map search service, it would have been a more perfect lecture. If you add it in the future, I think more people will take the lecture. However, it is a very good lecture because you can learn how to use the API in less than an hour, You can finish studying in 1-3 hours what would take at least a week if you study from a book, You can look forward to the next lecture because the lecture progresses neatly, etc.!!