@FIZZ! could we have a fizz app for mobile service (other than internet)?

You can make a shortcut in your desktop or if you have android with google chrome it will propose to do it for you.
I know, it does not answer completely to your question, but probably this is a way to keep de service a low cost

Fizz will never create one, they keep costs low, so that's why is cheap.

As well for security reason, the web is more secure!!!