I will recommend you to follow some guidelines over world wide web and search for some complete tutorial how to do what you are looking for. I am not sure you will have answer to your questions in simple words.
Yes you read that correctly, PHP is coming (well itís here) for Android. Irontec is the company behind the project and their aim is to make PHP development in Android not only possible but also feasible providing tools and documentation. Youíll need a few things before you can dive into this, One being ASE or the Android Scripting Environment:
oh, i thinks this web help you very much.
This is online course about Essentials of Android Application Development. http://bestcoursehub.com/home/index....n-development/
In this Essentials of Android Application Development, Android developer Ian G. Clifton takes a tutorial-style approach to teaching the viewer how to work with all the essential parts of the Android SDK.
Look at http://phonegap.com/. The approach is that you have your current website with all its data, then you essentially make a website that "talks" to your main php website for its data that you wrap up using Phonegap so that it can be deployed on to Androids and iPhones.