Application on android\ios in a short time?

Question

Software porting

Good afternoon!
There is a task to develop an application for android and iphone.
What should be in it:

• User registration,
  
• Two goods
  
• Checkout Page
  
• User profile
  
• Displays existing/completed orders
  
• Displaying a page of information about an existing order
  
• Dynamic dropdown lists - that is, the number of elements in them changes
  
• Server communication
  

Essence: The
user registers in the application, gets to the page with the choice of goods, selects, clicks on order, gets to the order page, where he selects the number of orders, type of delivery, and, depending on the type of delivery, enters the phone number, address and date, or selects a warehouse, pickup date and phone number. Press to issue. After that, it goes to the main screen.
He can go to the profile page and edit information about himself there, see information about orders. By clicking on the order, he gets the opportunity to see all the information about it.
There are already all the graphics, a server and even a small web version (it is planned to organize an admin panel in it).
I can: c#, a little java, a lot of frontend (js, html, css), a little php.
Actually the question is:
You need either some kind of multi-platform engine, or cases of porting a site to a mobile application.
Googled, but there is little useful information, maybe someone has real experience.

Answer 1

Why do you need to describe the project? There are several options to make a mobile application
- React Native development
- Hybrid (Atom, Xamarin)
- Native development

Answer 2

Do it all on the server + high-quality mobile layout, and then use some kind of wrapper that will turn this web into an application, there are a lot of them.