I don\'t believe there is any solution to hide bars programmatically using javascript/css/html, but let me try to describe a problem. We are the team of mobile game develope
This solution worked for me, but in my case, the webapp was for a private public, where I had control of the Ipad that would be used.
I tried to use all possible meta tags and hacks, and really, after IOS8 have removed the minimal-ui feature, was practically impossible to solve.
Thinking outside the box, our team reached a nice solution:
The Mercury browser opens in fullscreen, and even when pages are being charged, the address bar does not appear. It is a small icon on the bottom right and only :) It worked perfectly for our problem!
But I repeat: do not use it if you are developing a webapp for the public in general. It's terrible for the UX force your user to download a different browser to access the app.
UPDATE
A developer friend of mine came up with this solution:
Use a webview inside of Titanium from appcelerator. It won't be aproved on Apple store, but for a private event, it'll work just fine!