keymanapp/keyman ? reverse-engineered prompt

Build me a cross platform typing app that lets people type in different languages on Windows, macOS, Linux, iPhone, iPad, Android, and in a web browser.

I want it to feel simple for users, like they can pick a keyboard, start typing, and switch languages easily. It should support custom keyboard layouts, and there should be a way to create and load those keyboards so they can be shared with other people. Make it look clean and reliable, with the main focus on helping people type correctly in their language.

If you need to check current docs or platform details online while building it, go ahead. Please set it up so the core typing experience works across the different platforms, and keep the code organized so it can grow over time.