Is it possible to build React Native for iOS without a Mac?

https://www.macincloud.com/ might be of interest.

You could install macOS on a Proxmox Server[1]. It's a hell of a procedure and probably more work than just getting an old MacBook Pro 2015 using OpenCore Legacy Patcher[2] to install current macOS.

Once you got it working (signing keys etc.), you may be able to use github actions to build and publish your stuff without having a mac present. Unfortunately it won't work forever, so probably it is the easiest way to buy a mac.

[1]: https://www.nicksherlock.com/2022/10/installing-macos-13-ven...

[2]: https://dortania.github.io/OpenCore-Legacy-Patcher/

It's not possible without an Apple Developer account and signing keys.

Even side-loading an app for a short time for testing requires the app to be digitally signed.

Publishing to the App Store means the app is digitally signed by a valid Apple Developer account and that the app has been reviewed to meet the App Store requirements and guidelines.

I highly suggest you look at Expo and EAS, it is dead easy. I have no affiliation, just a previous free->paid->free user.

Depending on what type of features/entitlement your app needs, it might be worth virtualizing it, buying a cheap/used Mac, or renting a Mac in the cloud for *testing*, but you don't need one to write, test, or submit it to the App Store.

You don't technically need an iPhone either, you can assign others to test in TestFlight.

Unfortunately you will need the $100USD/year membership vs Google's one-time $25, but ya gotta pay to play!

Expo Submit:

https://docs.expo.dev/submit/introduction/

I guess using Expo app ?

Kotlin Multiplatform.