What is the best approach to developing an iOS application with an existing website?

Question

Mobile development

I am currently developing a new VPN service, and in fact the site, along with all the backing, is already fully operational. However, before the release, we made the decision to also make an iOS application in order to increase the reach and make it easier for more people to use the VPN. Complicating the task is the fact that it’s impossible to limit yourself to a direct conversion of a site into an application, since userflow is noticeably different for a mobile device. For example, .ovpn configs are downloaded on the site, and in the application it should be automatically imported into the system and included.
In this regard, I would like to address the experts with the following question: How would it be more correct to approach the development of a VPN client? Should I write a completely native application from scratch, or take, say, something like Flutter / React Native, which will later help to make an application for Android as well? The main requirement for the application development method is the ability to use the system API to manage VPN configurations (OpenVPN and Wireguard in the near future). All other functionality is quite simple, and most likely will be implemented in any framework / language.
Also, to save time, it would be possible to simply embed the site in the application for some functions (something like an iframe?), This is definitely suitable for payment, since the UI and UX are the same for the site and the mobile application.

Answer 1

Should I write a completely native application from scratch, or take, say, something like Flutter / React Native, which in the future will help to make an application for Android as well?

Well, it's up to you to decide)
Both methods are viable, both have their pros and cons.

The main requirement for the application development method is the ability to use the system API to manage VPN configurations (OpenVPN and Wireguard in the near future). All other functionality is quite simple, and most likely will be implemented in any framework / language.

This is usually easier to solve with native platform tools than trying to generalize

Also, to save time, it would be possible to simply embed the site in the application for some functions (something like an iframe?), This is definitely suitable for payment, since the UI and UX are the same for the site and the mobile application.

Everywhere there is a webview