PhoneGap applications are designed to host Single Page Applications (SPA).
This is where a single HTML page with it's supporting resources such as javascript and css files are bundled into a package and downloaded to the phone. PhoneGap provides a native wrapper to allow your Javascript code to access the phones native API's. Extended functionality is made available through the PhoneGap plugins.
This allows the SPA to work offline as all its resources are embedded on the phone.
PhoneGap now works using NodeJS which can be difficult to set up. If developing for Android you also need the ADT kit and to install ANT. WindowsPhone has it's own problems setting up too.
The PhoneGap get started page will take you through setting up the PhoneGap dependencies.
PhoneGap Platform Guies[
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There are many tutorials on PhoneGap development but a good YouTube series starts here:
https://www.youtube.com/watch?v=0gGBhaVG9CI[
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Apple will reject any application which uses PhoneGap to load an internet hosted website as this creates an uncontrollable risk for them. But you can use AJAX within your SPA to access internet hosted data.
Although Apples enterprise licensing model doesn't suffer the same restrictions if your distributing your application internally within your organisation.
I've produced PhoneGap projects with the SPA approach. You can then use jQuery (Or any other AJAX approach) to to call your REST API.
How to consume a RESTful service using jQuery[
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