How to turn the appendix on Apple iPad into the program for Mac

In June of this year, on WWDC, Craig Federigi artistically and with examples told about something very important. Thanks to what to macOS returned Twitter, and there were Jira and Asphalt. But the most important was not told about the reason of these miracles. That nobody doubted importance and the value of this reason, in macOS 10.15 arranged...