Hello, experts…
Thanks for everything you done for us.
As I have a shop, clients need to open the app to order and thats easy to make, the only thing I need to know is how to have an order number for each order they make?
order number should be showing up and has to be unique from other order numbers after the client submit their order, and later on can be returned from the data base. in swift, how can I make different order number for each order they make?
Hi @EngSamer and welcome!
I am not “an Expert” but happy to help!.. 
How do your customers placed their online orders now?
Do you have any online shop yet?
The way to do with an app would be to use it to connect to the main website to place the order using API/JSON communication (as your main database would know stock availability and etc…).
But the question would be “What is the exact needs for an iPhone app?”
Is the website not sufficient?
If you already have a great online shop and want an app for marketing purpose but not necesarely want to spend time (and/or money) creating a complex one, you could just create an app embedding your website. Very easy and very simple to put in place.