So I have a simple jQuery Mobile site interfacing with a MySQL database via PHP. Users orders are queried initially, then updated using the mobile web interface. I am not using any PHP framework, just 7 or 8 PHP files I've written for retrieving, updating, creating, and deleting order records.
As I begin to develop the Android and iOS applications, I realized it would be beneficial to have a PHP backend framework that can handle requests to create/read/update/delete my orders and users records from any of the 3 sources without caring which one it is. I want to create a layer of abstraction between the server side database handling and each of the 3 mobile interfaces. I envision being able to make a POST call from the client side, passing a TYPE argument and a JSON array of the data to a generic page like /myserver/mRequest.php, which would determine what to do based on TYPE and handle the processing, returning a STATUS variable and a JSON array of data back to the client.
Is there a good (preferably free) PHP framework that will help layout the backend? I've looked at Zend and a few others, but they seem pretty heavy and intended for desktop sites. I want to minimize the number of calls to the server as well as the amount of data thats sent back and forth (we all know how slow Verizon 3G is).
I'm hoping theres some lightweight framework out there that can be a skeleton for me to organize CRUD functions, check for null values, handle MySQL errors, etc...
If not, a guide to developing a PHP mobile backend would be the next best thing.
Note: I apologize it there is a thread already asking this, but I couldn't find one that I thought fit.