Hi, everyone, I'm a new member here.

Currently, I'm developing a web application and there's a need to make an activation for the product I developed. I want give activation on my product for a time session on local. My question is, is it possible to make that? As we know, there are a lot of desktop softwares required activation through internet or by phone (and it seems the softwares write to the registry too) but I never see web application do the same thing. Maybe one of you ever make something like that?

Thanks in advance.

I have recently been looking into this. There are a couple of free options to generate keys and so forth but the actual activation is probably additional development if you want to automate it.
This is a pretty simple approach

There was oriiginally built for VB but there is a PHP version. I did a bit of initial testing. It looks as if it is made for PHP4. It will take a bit of work to make it PHP5 compatible (but it may be worth it).

or if you are prepared to pay for it, you can look at:
PHP License Pro
This includes activation and monitoring.

You are going to have to protect the code as well so you will probably want to use Ioncube by purchasing a copy or uisng their online pay as you go option. You can use an obfusticator but they can be broken so you probably don't want to do that for anything that you've invested a lot of time into.