The development cycle is basicaly this: write Typescript code in a .ts file, transpile to a .js file, load .js into html. Transpiling can be handled by the IDE or by a build tool like gulp. For example, IntelliJ Webstorm has a built-in file watcher that tracks changes to .ts files and transpiles accordingly.

Typescript can be debugged on a source code level, using source-maps. Webstorm and VS Code have built-in or plugin solutions. I heard some people complaining about issues, but i had a pretty smooth experience so far.