Share to download Facebook + PHP

Question

I've just build a facebook app for my band. We would really like to share some free music with fans, but it would be great if they'd share the page first before the download is available.

So in short:

User visits special tab on facebook page -> clicks share for free download in this tab -> goes to share page screen -> gets redirected to download page after pressing share / get redirected to error page when presses cancel

I know this is possible, I just have no idea where to start. Anyone here has any experience with this and would like to share it with me? I tried to search for the answer, but I couldn't find any detailed up-to-date information.

Thanks a lot for your time!

Answer 1

Have you considered going for an already done app ? there's plenty of them around, for example:

http://www.tabsite.com/help/page/333/Friend-Share-Deal-Download-App

HOW DEAL DOWNLOAD CAN BE USED BY FAN PAGES:

Visitors to the Page tab must first share the deal with a friend, then they get access to the download.