Right now if you don't have cocoapods installed we will (silently) set it up for you as part of the pod install run as part of flutter run. This first install can take 20 minutes. :/

It seems like it would be better to separate setup from running so we don't have a bad first-run experience.

%rm -rf ~/.cocoapods
%flutter run

Launching lib/main.dart on iPhone 6s in debug mode...
Running pod install...                                    
CoreSimulatorBridge: Getting container class internal daemon!

It's just hanging checking out cocoapods:
32981 ttys000 0:00.02 /usr/local/git/current/bin/git clone https://github.com/CocoaPods/Specs.git master --progress

I think a better experience would be to just fail instead of silently installing. @mit-mit