Notedog – Portable Git-Friendly Markdown Journal

An Android app that lets users journal in Markdown without sync services or lock-in, editable from phone or web browser on the same local network. Appeals to privacy-conscious users and those wanting offline-first journaling.

Obsidian already owns the "plain-text, no lock-in, privacy-first" positioning and has a loyal developer audience, making differentiation genuinely hard — the Android app gap is real but Obsidian is actively closing it. The offline-local-network sync angle is niche enough that it appeals to a specific kind of technically literate user, but that same user is likely to just self-host Joplin or configure Syncthing with their existing notes app rather than pay for another one. At $200–1k/mo, this probably lands on the lower end of even that range — one-time paid apps in this category struggle to hit recurring revenue, and the privacy-first crowd resists subscriptions harder than most. The biggest risk is that the addressable market is small enough that even with zero churn, the ceiling is a side-project income at best, not a business.