If you're a developer sketching architecture or conducting quick brainstorming sessions, Excalidraw is your best choice. Its charming hand-drawn aesthetic is perfect for low-fidelity sketches, and being free and open source allows for easy self-hosting and local data management. However, if you require polished visuals or a comprehensive design tool, Excalidraw falls short.
On the other hand, if you’re part of a product team or looking to build custom canvas apps, tldraw offers a more refined infinite canvas with real-time collaboration features. The ability to turn sketches into working UI adds significant value for developers. However, if you only need a simple free sketchpad without the commercial use in mind, you might find tldraw’s freemium model less appealing.