Hiii friends i heared we can develop android application using PHP…but i dono idea about that please assist me…if u have any link or ebooks send to my mail id...rajeshnayak2003@gmail.com
PHP is a scripting language, you will still have to run it through an interpreter somewhere along the line, aka.seb server, which means you are just making an application that is viewable via the android device’s web browser… This is also known as a standard web application 
If you are going to design a web application able to work on Android. I can use PHP to serve the pages and you will likely need CSS Media Queries to target the appropriate screen sizes.
Steve
You can create php coding for geting values from the db, but to make it accessible by an android app you should use API`s.
Your api should not be so complicated just pass the values using array and format it through JSON or a SOAP which will communicate with the .apk files and help to display the datas…
if you have further doubts check “php using JSON” on google, where you`ll get some fine examples…
I haven’t tried it, nor do I know if applications (through the market) is possible, but you probably can use Android Scripting Environment aka SL4A (http://code.google.com/p/android-scripting/) and use the PHP plugin: http://phpforandroid.net/