Compare software

Slugline vs Trelby: catalog facts
Slugline	Trelby
Freemium Free up to six pages per script; longer scripts need the Unlimited Writing upgrade.	Free Free software under the GPL.
macOS, iOS	Linux
Automatic screenplay formatting as you type Drag-and-drop outline that moves the matching script text	Enforces correct screenplay formatting and pagination Imports and exports Final Draft and Fountain files
Apple platforms only Scripts longer than six pages require a paid upgrade	Interface built with wxPython looks dated next to commercial tools No collaboration or cloud sync features mentioned
Downloadable app	Downloadable app
Closed source	Open source
License not stated	License: GPL-2.0
Not stated if an account is needed	No account needed
Not stated if it works offline	Works offline
Official website Full listing and sources Checked October 2, 2026	Official website Full listing and sources Checked October 1, 2026

Catalog facts only. Anything “not stated” is unconfirmed. Check full listings for details.