How do I handle session PHP with appinventor?

Hi guys, I'm realizing a login system with Appinventor and a remote server MYSQL, but I don't know how to use sessions with appinventor.
I tried to use session_start() in the file the check the data and in the one that should welcome the user, but it doesn't work.
What should I do to make it work?
kind regards

& Use the web component to communicate with your php server

In which way should I implement it?

This is not really an AI2 question, you may have more success asking in a php forum?

The web component simply makes GET and POST requests and returns the server output. You need to understand what you need to send, and what you expect as a result. Your php files will need to be configured correctly in order to handle session requests. I do not know enough about php sessions to be able to help further...

You may want to show us what you have tried so far (images of blocks, urls/parameters, etc.)