http://stackoverflow.com/questions/33315753/installation-failed-with-message-null-genymotion-error
Installation failed with message null.
It is possible that this issue is resolved by uninstalling an existing version of the apk if it is present, and then re-installing.
WARNING: Uninstalling will remove the application data!
Do you want to uninstall the existing application?
貌似是模擬器沒啟動完成就運行應用導致的；等模擬器啟動完成再運行應用。
http://stackoverflow.com/questions/15524185/could-not-access-the-package-manager-is-the-system-running-while-installing-and
https://code.google.com/p/android/issues/detail?id=62113