This project was ordered by Mr. Farshid to do for him. The project was designed to allow users to log in and send letters to other users with their own usernames and passwords. But the letter had to be encrypted so that it would not be possible to manipulate in the database or even by admin itself. So after the end of the letter, the encryption information was presented to the user in hash and, of course, in the form of QR, as well.
The user could see his mail whenever he wanted, by scanning the QR from his mobile phone. Even if the letter had been manipulated, he would be noticed and so on.
When the customer wanted to order this project, I was texting him with Messenger. He was saying, I’m in a hurry. I chatting with him for about 2 hours. During our chat, I was programming what he had been ordered, simultaneously. (Without he knowing it.)
After the chat was over, I sent him a link. He said what’s this? I said: this is the project you want. I developed what you wanted. I wrote the project in two hours :-) He was surprised and liked my job so much. From that time, he was always working with me and was sending me any project he had for be programming.