What is code signing on iOS?
Code signing is how Apple makes sure an app comes from a known developer and hasn't been changed since it was built. The app is signed with a certificate tied to an Apple account, and iOS refuses to run code whose signature doesn't check out. Every app on an iPhone is signed, whether it came from the App Store, TestFlight or a developer's own build.
More about Code signing
Signing normally happens in Xcode on a Mac, with a certificate and a provisioning profile kept in the Mac's keychain. A missing certificate or a profile that doesn't match is a classic stumbling block for new iOS developers.
Code signing with Borel
You don't need a Mac or a keychain. For your own iPhone, Borel Companion signs the app with your Apple ID on your Windows PC or Mac. For the App Store, Borel signs the build on its own Mac with your App Store Connect key before it uploads it.
Related terms
Make your iPhone app in Borel
Describe it in your own words. Borel writes it in Swift, builds it on its own Mac and puts it on your iPhone.