The following steps may be needed to build and run Zulip iOS:
git submodule init
git submodule --recursive update
pod install
open Zulip.xcworkspace
you may need to disable bitcode in your project
http://stackoverflow.com/questions/31205133/how-to-enable-bitcode-in-xcode-7
if CocoaPods is not installed, you wil need to do so
sudo gem install cocoapods
before running
pod install