AppFlowy
Alternative to Notion, Team knowledge base, Knowledge Bases
Build detailed lists of to-do’s for different projects while tracking the status of each one. Open Source Notion Alternative.
Slowing down
AGPL-3.0
Every open-source task management & to-do lists project we track, scored on maintenance, momentum and licence — so you can tell the live competitors from the abandoned repositories.
Task Management & To-do Lists has 24 open-source implementations in this dataset, of which 9 show real momentum and 1 are dormant or abandoned. The leader is AppFlowy with 75k stars against a category median of 2.2k — roughly 35x the typical project. Saturation score 50/100: Contested. Several maintained alternatives exist, but no one owns the category.
Winnable, but differentiation is not optional. Pick one underserved segment and be visibly better for it rather than competing feature-for-feature with a free tool.
The practical test in this category: AppFlowy is the reference implementation at 75k stars, and 9 of 24 projects are still shipping. A buyer evaluating you will find at least one maintained free option, so your pricing and positioning have to answer "why not self-host AppFlowy?" in the first minute.
Alternative to Notion, Team knowledge base, Knowledge Bases
Build detailed lists of to-do’s for different projects while tracking the status of each one. Open Source Notion Alternative.
Task Management & To-do Lists
Advanced todo list app with integrated timeboxing and time tracking capabilities. Integrates with Jira, GitHub, GitLab, Redmine and OpenProject.
Alternative to Kanban board
Open-source Trello-like kanban.
Alternative to Kanban board
Realtime kanban board for workgroups (alternative to Trello).
Alternative to Kanban board
Simple visual task board.
Task Management & To-do Lists
Flexible kanban app that helps you organise work, track progress, and deliver results (alternative to Trello).
Task Management & To-do Lists
The to-do app to organize your life.
Task Management & To-do Lists
Single-page minimalist kanban board; compact, highly readable and quick to use.
Task Management & To-do Lists
Task management tool with hierarchical structure, smart recurring tasks, and seamless Telegram integration.
Task Management & To-do Lists
Task and chore management tool for personal and family use, with advanced scheduling, flexible assignment, and group sharing capabilities, detailed history, automation via API, simple and modern desig
Task Management & To-do Lists
A self-hosted, file based task management board that supports Markdown syntax.
Task Management & To-do Lists
Web-based application to help you implement David Allen’s [Getting Things Done™](https://en.wikipedia.org/wiki/Getting_Things_Done) methodology.
Task Management & To-do Lists
Straightforward realtime kanban boards management for intuitive task tracking. Featuring an elegant dark mode, collapsible todo lists, and multitasking tools to supercharge your team's productivity.
Task Management & To-do Lists
A tool to help organize ideas and build great things. Plan, organize, build and ship.
Task Management & To-do Lists
Track habits, tasks and notes with time tracking, calendar view and completion statistics.
Task Management & To-do Lists
Simple way to manage your todo list in AJAX style. Uses PHP, jQuery, SQLite/MySQL. GTD compliant.
Task Management & To-do Lists
Offline-first task manager with weekly planning, project boards, real-time sync, Vim keybindings, desktop quick add, and import from popular task managers (alternative to TickTick, Todoist).
Task Management & To-do Lists
Day planner with drag-and-drop time blocking, inbox, recurring tasks, habits, routines, goals, projects and Pomodoro focus mode, plus iCal and CalDAV calendar sync. Data stays in the browser, with opt
Task Management & To-do Lists
List editor for power users, backed by a self-hosted server.
Task Management & To-do Lists
Complete ecosystem for time management using the Pomodoro technique.
Task Management & To-do Lists
List management app for creating and publicly sharing lists of items. Supports auth, admin tools, item notes and priorities, and opt-in public read-only links with randomized URLs (alternative to Amaz
Task Management & To-do Lists
Simple shared list application including shopping lists and any other small todo-list that needs to be used collaboratively.
Task Management & To-do Lists
Taskwarrior is Free and Open Source Software that manages your TODO list from your command line. It is flexible, fast, efficient, and unobtrusive. It does its job then gets out of your way.
Task Management & To-do Lists
Minimalist single-user kanban todo app. Clean, simplified, and compact UI. Can import boards from Trello.
Existence is not competition. A project competes with you only if it is maintained, findable, deployable by your buyer and licensed for their use. Most projects fail at least one of those tests. Run all four before you shelve an idea — or before you assume you have a clear run.
Stars are a lifetime counter with no decay, so a project abandoned in 2022 still looks like a leader in 2026. In this dataset 149 projects are dormant, abandoned or archived, and several of them sit in the top decile by stars. Sort by momentum and commit activity instead — popularity tells you the project was once interesting, maintenance tells you whether it will still be there when your customer needs a bug fixed.
When a prospect says 'we could just self-host the free one', they are usually comparing your price against zero. The real comparison is your price against hosting, upgrades, backups, security patching, integration work and the engineer hours behind all of it. Quantifying that number is the single most effective response to a free-alternative objection — and it is more persuasive coming with a spreadsheet than with a feature list.
Founders treat licensing as a legal footnote and then discover it dictates strategy. Permissive licences allow closed commercial forks, which is why so many managed services exist around MIT and Apache projects — and also why your differentiation cannot be the code itself. Copyleft licences, especially AGPL, remove the closed-wrapper option entirely, which reduces competition but restricts you too. Source-available licences exist precisely to stop the wrapper business.
Search this database by category and by the commercial product you would replace. It covers 1665 projects across 130 categories, each mapped to the paid tool it substitutes. If your category shows a "Crowded" verdict, a maintained free version almost certainly exists and your positioning has to account for it.
No. It means free is your price anchor. Plenty of large companies were built next to a good open-source project — the ones that failed were the ones selling the same job at a price the free tool made indefensible. Find the part of the job the project deliberately does not do, and sell that.
Each category gets a 0–100 score built from three inputs: how many implementations exist, what share of them are still actively maintained, and how far ahead the leading project is compared with the category median. 62+ is Crowded, 38–61 Contested, under 38 Open. 11 categories are Crowded and 88 are Open.
A project has momentum when it committed code in most of the last twelve months, shipped a release recently and is not archived. 736 of 1665 projects qualify. This is the single most useful filter here — it strips out the popular-but-dead repositories that make a category look more competitive than it is.
It depends entirely on the licence. MIT, Apache and BSD let you build and sell closed products on top. GPL and AGPL require derivative work to stay open, and AGPL extends that to network use, which blocks most SaaS wrappers. BSL, SSPL and Commons Clause are source-available, not open source, and usually restrict competing commercial use outright.
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