While filling out HTML formulars, the iPhone Keyboard has a black bar on top with the buttons "Back", "Next" and "Done". This bar isn't present on native apps.
I would like to know if there is a way to change the iPhone layout on a webapp in order to hide the bar?
Although I have no intention to verify this but it is my belief that you can not change how iOS puts a field navigation bar when the keyboard is displayed in Safari. I tested in a few web apps out there (notably gmail) and it is there as well.
In iOS app development that bar that Safari puts above the keyboard is a view that the application puts there not something the content (your web app) creates or has access to.
Unfortunately the only way I know of is to create your own iOS native app and have it load the web app. (See mailroom app for an example).
No, you can't. What you see there is Safari's implementation of entering text in text fields and tabbing through all of them (as there is no TAB key present).