Building a web+mobile cross-platform app in Ionic 2?

I searched the forum for this topic, but I could only find threads that were written about Ionic 1 years ago. Anyway…

I’d like to write an Angular 2 web app and an Ionic 2 mobile app, in TypeScript, sharing as much of the codebase as possible. With Ionic 2 being so heavily based on Angular 2, it doesn’t seem like it should be too difficult.

Has anyone accomplished this and have any advice on how to go about it and things to watch out for?