How to deploy webservice

I now have a website (joomla do), I should let him how to deploy webservice to interact with the mobile client ah?

Php write some interfaces with the database and then use them for export jason, etc. This mobile phone client to read it?

Thank you enlighten ah


Reply:
Open several Action, ordained query parameters. Then tested using ordinary PC browsers look to export Json.
Reply:

Your phone is understood as the browser has become, what you echo, mobile application on what to get
Reply:
I saw the mobile client requests are html, get jason or xml.

These things should be how to deploy the server side, the export on the line?