Free Web Apps
27 browser toys and tools, with the build notes for each
What it does
27 small things that run in a browser tab. No install, no account, no build step. Open one and it runs. Next to each one is a write-up of how it was made, and the write-ups are the point: the section that matters is usually "the place it goes wrong", because that is the part nobody warns you about. 23 of them we wrote by hand. 4 were built by describing them in plain words, and for those we kept the actual transcripts — dead ends included. We keep the two lists separate.
Every app on this page was built by describing it in one sentence. Open any of them, use it, then fork your own copy and change it.
Everything on this page is a live app — not a screenshot, not a video. Open any of them and use it. Then fork it and change it by saying what you want different. Most open straight away. A few need a sign-in because they save data or call an AI, and those are marked. Written by us and left open on purpose: real physics underneath, every number worth changing gathered at the top of the code. Fork one and it's yours to take apart. These ones weren't hand-written by anybody. Each was built by describing it in a sentence and letting the AI do the work — the same way yours would be. Every app here is open for remixing. Fork it and you get your own copy — the whole project, code and all — that…from ahcoder.tybbtech.com
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