[zoomerang]

For simple apps, HTML5 works fairly well. But you quickly run into problems.

My company has been working on a cross mobile application in HTML5 using Cordova. It was quick to prototype, but as we scaled up we started hitting the limitations of the platform very quickly.

The main issue is that every single mobile device has a slightly different rendering engine. Even two different Android phones from the same manufacturer will behave slightly differently. If you're making a simple CRUD app, this probably won't affect you - but once you reach a moderate level of complexity you spend more time playing whackamole fixing bugs and testing on every possible combination of devices.

We're currently rewriting as pure native across all platforms, since it works out to be less effort in the long run.

This is on top of the obvious limitations of HTML5 - Performance is never quite there for anything other than trivial tech demos, and the lack of native widgets mean your users will have that "uncanny valley" experience where it doesn't quite feel right.

tl;dr HTML5 is ok for prototyping and simple apps, but doesn't scale well. Ditto for Javascript.