Build lags for a full minute on "Performing Install Actions"
Fix : Turn off iPhone wifi. restart it and install the app now. Now you turn on the wifi. and it works. Fixed.
I recently ran into this problem and resolved it by restarting the device. I have no idea of what the cause is so I am reticent to suggest this is a universal solution but it did work for me once in a row.
I've been dealing with this same thing, but connecting the phone to WiFi seems to unblock my installs. Who knows why... but give that a shot if you're still running into this issue.