Managing Multiple Open Files Using the Tab Bar
You can open multiple files at the same time and switch between them using the tab bar.
When you open a file, it is opened in a transient (or temporary) tab, indicated by the italic title and the Pin button on the right side of the tab.
To make the tab stay when you open another file, tap the file title or the pin button at the right side of the tab. The file is also kept open if you tap on the editor or open the same file by tapping on it a second time.
This is very similar to what desktop code editors like Sublime Text, Visual Studio Code, Atom and TextMate do: in those apps, files are only kept open if you do double-click them. This is done so that you don’t end up with many, many tabs when you are just browsing a project.
Drag tabs to reorder them.