taking php and converting it to xml for android app

taking php and converting it to xml for android app

I know this is probably a dumb redundant question. However i found so many
ways to do what i am looking for i just want to know the best way of doing
it.
I am building a simple multiple player game for the android platform. I
have PHP and MYSQL as the server back end. The back end works perfectly.
Now what i need is to send a few simple variables and receive some data.
The app is a basic scorecard. It has the players in the first column
labeled name. The user adds a set of columns with their own custom name
from a script i have made.
I need to send the game id from the server and the row id for the users
name. Also i need to receive the column names the user has chosen, and the
updated score so i can add it to their row/column
//The variable i am using for the the game id is $pw
// Also the variable for the row id is $userid = pid
// and for the column names i am receiving are formatted as follows $loc1
= location A, $loc2 = location B, $loc4 =location C etc.
From the research i have done i need to be using XML with cURL or SOAP.
If you need more information please let me know. The question i am asking
is what would be best to use to get the data from my server to a android
phone and back. Also in the future i plan on making it work with I phone
as well. If you can please provide some helpful links, or code i would
greatly appreciate it. Thanks.