Madoko is described as 'fast markdown processor for writing professional articles, books, manuals, webpages and presentations, with a focus on simplicity and plain text readability'. There are more than 50 alternatives to Madoko for a variety of platforms, including Mac, Windows, Linux, Online / Web-based and Self-Hosted solutions. The best alternative is Joplin. It's not free, so if you're looking for a free alternative, you could try Mark Text or StackEdit. Other great apps like Madoko are Typora (Paid), Haroopad (Free, Open Source), HackMD (Freemium) and Inkdrop (Paid).
Joplin is a free, open source note taking and to-do application, which can handle a large number of notes organised into notebooks. The notes are searchable, can be copied, tagged and modified either from the applications directly or from your own text editor.
Haroopad is a markdown enabled document processor for creating web-friendly documents. You can author various formats of documents such as blog article, slide, presentation, report, and e-mail as if experts did.
Marp is the simplest presentation writer with Markdown. FEATURES Create slides by Markdown Cross-platform Live preview with 3 modes Theme supports (Default & Gaia theme) Export slides as PDF! Write the presentation with like a feeling of Markdown editor.