Monogatari is described as 'simple web visual novel engine, created to bring Visual Novels to the web'. There are five alternatives to Monogatari for a variety of platforms, including Windows, Linux, Mac, Online / Web-based and Android. The best alternative is Twine, which is both free and Open Source. Other great apps like Monogatari are Ren'Py (Free, Open Source), Ink by Inkle (Free, Open Source), Naninovel (Paid) and Yarn Spinner (Free, Open Source).
Document-Based Scripts Designed for scriptwriters, naninovel scripts — unique feature of the engine — allow developing complex text-based adventure games using familiar text editors. Write stories, not code!
Yarn Spinner is a tool for creating interactive dialogue for games. Write your conversations in Yarn, a simple programming language that's designed to be easy for writers to learn, while also powerful enough to handle whatever you need.