What are some alternatives?
Prezi - Welcome to Prezi, the presentation software that uses motion, zoom, and spatial relationships to bring your ideas to life and make you a great presenter.
Reveal.js - A framework for easily creating beautiful presentations using HTML
Keynote - Keynote for Mac, iOS, and iCloud lets you make dazzling presentations. Anyone can collaborate — even on a PC. And it’s compatible with Apple Pencil.
Sozi - Sozi
LibreOffice - Impress - Impress is a truly outstanding tool for creating effective multimedia presentations.
Powerpoint - Explore how PowerPoint can help you tell a powerful story in your presentations and easily share your slides on the web.