For Sublime, Atom, etc. there are a bunch of plugins that you can download:
https://github.com/Microsoft/TypeScript-Sublime-Plugin
https://atom.io/packages/atom-typescript
Check out the DefinitelyTyped (http://definitelytyped.org) and Typings (https://github.com/typings) for type definitions to most of the popular JS libraries. There is also a list of some useful tools and utilities on the DefinitelyTyped website but here are a few that might be useful:
https://github.com/palantir/tslint
https://github.com/sebastian-lenz/typedoc
For a few reasons, we chose Xamarin to build the Kato mobile apps. The end result was pretty good—great, even, considering the ridiculously tight timeline. We had a pretty elaborate common core with all the hard stuff (networking, caching, protocol, presence, etc), and custom UI code for Android and iOS.
In the end, since Kato was to be no more, the real benefit was seeing how much sense it makes to use a strongly-typed, object-oriented language for building complex user interfaces.
Many years ago, and for many years, we were C#/C++ programmers, so it wasn't exactly a revelation. But, we'd been working for quite some time with dynamically-typed Erlang and dynamically-typed Javascript (the Kato UI was built with Knockout.js).
Our server code was fairly straightforward and didn't change very much, so Erlang was an excellent choice there. With JavaScript, we'd programmed our way into some serious debt.
When deciding on a stack for Sameroom, we embarked on a quest to replicate the Xamarin experience for the web. We eventually narrowed in on Flux, React, and TypeScript.
After some experimentation, we got a development workflow working with gulp, shrinkwrap, make, and no particular IDE (we use Atom, Sublime, and Vim).
The biggest crutch was lack of JSX support in TypeScript, so splicing together HTML elements was pretty cumbersome. We viewed this as a temporarly incovenience, which was a good decision—TypeScript 1.6 got React/JSX in September 2015 [2].
We're pretty conservative about adding dependencies, but the overwhelming majority of libraries we do use have TS support available from the DefinitelyTyped project [3]. The few libraries that weren't supported (Stripe checkout and Intercom, if memory serves), we TypeScriptified ourselves.
As a result, working on the Sameroom UI is absolute joy.
It's a little ironic that, unlike Kato, Sameroom basically doesn't need a UI, since it's just marketing copy and an administrative dashboard.
[1] https://sameroom.io/blog/from-pivot-to-140-paying-customers-...
[2] http://blogs.msdn.com/b/typescript/archive/2015/09/16/announ...