A significant factor in deciding on iOS app development cost is the type of app that you are developing.
Number & Complexity of Features
It wouldn’t be fair (or logical) for an iOS that uses Virtual Reality and one that doesn’t cost the same amount to be developed.
Device Support
Another critical factor influencing the cost of iOS app development services is the number of devices the app should support.
App Design
There is no hiding the fact that your users will instantly deliver a verdict of your app based on what they see.
Integrations
Integrations involve third-party solutions that can provide your app with additional functionality because of the exchange and transfer of data between two servers.
Types of API
Applications that offer a service or a product for sale would require payment integration and probably a shipping API as well to integrate shipping details.