You need osx with xcode installed to build it
Use scripts/fetch-projects.sh
to fetch engine with dependencies
Run scripts/fill-project.sh
once before build
Remove all except dummy.c from empty before committing changes to xcode project (you need it to fill project again after engine update
Use scripts/run-xcodebuild.sh iphoneos armv7 output.ipa
to build engine with prebuilt game libraries
By default, gamedir used, but may be overrided with Library Suffix option