Auto Facebook Invite (open to best practice: web app, ios app, android app, java app)

We need an application. (Any of the following will be fine with us: Web application on php, or microsoft .net ios application android application) the application will have permission to access pages that a given facebook user has admin control over) the application will auto invite people to like pages if they perform an action on the page. Admin must be able to turn the app on/off for specific pages admin has access to as an admin that's it. Please respond with 1. your experience that will help you complete this project proficiently and on time 2. recommendation on what type of app to do this with. (as well as whether you are capable of building all 3 apps types) 4. how much time it will take before you will have a beta version ready to test.