One thing that I’ve found useful from a similar project in Android was the check for @Nullable/@NonNull that is possible to add everywhere and it’s being checked by Android Studio.
For objective-c and iOs Xcode checks for nullable/nonnull for method calls and returns, but it won’t check for variables used in methods.
I’ve looked around and only this abandoned tools seems to be doing that: https://github.com/soutaro/nullarihyon
I’ve searched for the rules used for Objective-c for SonarSource here https://rules.sonarsource.com/objective-c and did not find any mention for nullable/nonnull
Just wanted to confirm if that is the case or not.