While Apple doesn’t provide an “official” way to launch an app in the iOS Simulator from the command line, there’s a few private tricks we can employ. First, the iOS Simulator app itself is located in:html


But running that will only bring up the simulator in the last state it was in. How do we install an application in there and then run it automatically like Xcode does?ios

The trick is in the private iPhoneSimulatorRemoteClient.framework.
Now before you freak out, don’t worry! This isn’t something you compile your app against and submit to the store. This is a framework that we can use on our local machines to control the simulator just like Xcode does. The best part is, all the work of hooking
into it has been done for us!git

There are two command line utilities I’ve seen that do this best. I used to useiphonesim and
it works great. But I recently switched to WaxSim since
it also records video of the simulator in motion. They both are functionally equivalent and small enough to understand. It’s your call, but I recommend the later.1github


First, we need to pull down the WaxSim source and install it. Run the following:shell

git clone
cd WaxSim
xcodebuild install DSTROOT=/

Now, you have the waxsim binary in /usr/local/bin which
should already be on your path. You can now invoke your application in the simulator like this:xcode

waxsim [application path]

So, where is your application path? That depends on how you build it! First, we’ll need to do a quick walkthrough about building Xcode projects from the command line.bash

cd into your iOS application’s project directory (the one with the
Xcode project file). Then, invoke the xcodebuild command like so:app

xcodebuild -sdk iphonesimulator5.0 \
           -arch i386 \
           install DSTROOT=/tmp/MyApp

For most projects, this command will work just fine. However, if you have an explicit workspace set up, you’ll need to use man
 to learn how to teach thexcodebuild binary to interpret
your setup. There’s a lot of good stuff in there about how to specify whether to build for the simulator or device, too.iphone

The DSTROOT environment variable on the command above is the most important
part. DSTROOT is used by Xcode when run with the “install” build action
to figure out where to put the results. We’re specifying /tmp/MyApp explicitly
so that we know where the resulting application bundle will be to hand in to waxsim.ide

Once the xcodebuild command completes, you should now have an *.app
bundle in /tmp/MyApp/Applications/[YourAppName].app. Of course, subtitute
your own application name in the path. Invoke waxsim and you’re up
and running:

waxsim /tmp/MyApp/Applications/[YourAppName].app

This runs the iPhone simulator with the latest SDK that waxsim is aware
of. Usewaxsim -h to find out other options like running the iPad simulator
or other using other available SDKs.

You can also record a low resolution video of the simulator like so

waxsim -v /tmp/MyApp/Applications/[YourAppName].app

And now you’ll have in the current directory. It’s a pretty
low res and stuttery video, probably not something you’d use for a promotional demo, but it’s a nice feature if you need to review results of automated testing workflows.


So, for completeness sake, here’s a shell script that you can modify to build and run your application:


# Tell bash to abort the script if any error happens
set -e


xcodebuild -sdk iphonesimulator5.0 \
           -arch i386 \
           install DSTROOT="$DSTROOT"

waxsim "$DSTROOT"/Applications/"$APPNAME".app

Drop this in your project directory and tweak to taste.


So, there you have it. We’ve built the waxsim binary, learned briefly
how to build with xcodebuild, and learned how to launch your application in the iOS simulator on demand and from the command line. Vive la Unix!