Since many smartphones do not come with a text editor installed as standard, we implemented it as a web app so that it can be used immediately.
The implementation is simple, just pasting an html textarea, but in most cases this is sufficient since it will only be used as a temporary area for copy and paste.
To open an existing file, press the "Open" button. On a desktop PC, the standard OS file dialog will open, and on an Android smartphone, the device's standard "file picker" will open. Only files in UTF-8 format can be read.
To save a file, press the "Save" button. On a desktop PC, a "Save As" dialog will open. On an Android smartphone, depending on the device, the file may be automatically saved to the "Download" folder, or a dialog box may open to allow you to set the save location and filename.