Is it possible to develop a fully-functional iOS app without using Xcode?

Developing a fully-functional iOS app without using Xcode is technically possible, but it would be challenging and not recommended for most developers. Xcode is the official integrated development environment (IDE) provided by Apple for iOS app development, and it offers a wide range of tools and features specifically designed for creating iOS applications.

While some developers may attempt to develop iOS apps using alternative tools and frameworks, such as React Native or Xamarin, these tools often still require the use of Xcode in some capacity. Additionally, publishing an iOS app to the Apple App Store requires using Xcode for code signing and submitting the app for review.

Overall, while it is theoretically possible to develop a fully-functional iOS app without Xcode, it is highly recommended to use Xcode for iOS app development to take advantage of its robust capabilities and ensure compatibility with Apple's guidelines and requirements.