What is the best way to protect php application ?

I am trying to figure out how to protect php application and doing a license for php applications, do you have any idea of what is the best ?

Best would be to try the verify-purchase api call to protect items sold through this marketplace.

http://marketplace.envato.com/api/documentation

http://codecanyon.net/searches?sort_by=created_at&categories=&type=forums&filters=&page=&term=verify-purchase&type_id=&category=

Probably have to figure it out how to protect it in some way yourself, because if someone posts a how-to here it would be easy to reverse it.

Nothing is 100%, anyone who knows php can get around any sort of protection that can be sold on these marketplaces.

Otherwise if you are making a program not for sale on this marketplace, and you don’t want the client to access the code, then http://www.ioncube.com/ is the best commercial way to go.

Make sure hosting environment supports ioncube.

I think a lot of the big guys like plesk and cpanel use this to protect their own source code / licensing system.