I'm trying to use xcrun simctl to boot a device and uninstall an application, but it hangs on the uninstall step
xcrun simctl boot <deviceudid>
xcrun simctl uninstall <deviceudid> <bundleid>
and it hangs on uninstall and sits forever...however, if i have the simulator already running and execute
xcrun simctl uninstall <deviceudid> <bundleid>
it works fine...but i'm trying to do this in a script without opening the simulator manually
This happens because when you use 'xcrun simctl boot ...' you are not getting a full boot of the simulator. Some services (including those provided by the system app, like install or launch) are unavailable in this mode.
If you want to script booting the device in full, you'll probably want to refer to my answer in Xcode 6 - Launch simulator from command line