What Scrin does today

It does

Opens in your browser, with no account. Works offline after the first visit.
Brings in Word, Scrivener, Markdown, plain text, RTF, ODT, EPUB, HTML, Fountain, Final Draft, yWriter, and PDFs that carry text.
Takes your text out as Markdown, Word, EPUB, HTML, or PDF when you print.
Counts a script in pages, estimated, and takes it out as Fountain.
Saves a plain-text copy every day.
Keeps a scene’s history, so you can go back.
Follows you across paired devices: your first book, encrypted. Other books stay where you began them.
Shares a read-only link in someone’s name, no account needed. You can take it back.
Keeps a reader’s note on its passage, even after you change the text.
Draws the map of a manuscript, once you say yes.
Plans on a free board. Moving a card changes the manuscript only when you apply it.
Runs in English, French, German, Spanish, Italian or Portuguese.

An installed program outside the Mac: other devices use the browser.
Images and table grids on import. From Final Draft and yWriter, formatting stays behind too.
Scanned, damaged or encrypted PDFs. From Pages or Google Docs, export a Word copy first.
Screenplay layout as you type, and printing in script format.
The map and the free board on phones.
In the Mac app: several manuscripts, reader links, the map, updating itself.

Safari clears a site’s data after seven days of use without a visit. Keep an export, or pair a second device.
A book begun in a browser stays there until you move it to an app: pair them, or export and import.
Until you pair, share a link or ask for a map, nothing you write leaves your device.