Moto E Not Starting Properly After Changing runtime to ART I have recently bought a MOTO E and it's working cool. Then I have enabled Developer options and changed my runtime from Dalvik to ART. Afterwards I restarted my device. I got the message saying Android is upgraging. After completeing the process I got exceptions like 

unfortunately the process com.android.phone has stopped


Please help me how to get out of this problem. I am getting that message for around 10 times and mobile restarting once again.
/data/property/persist.sys.dalvik.vm.lib contains the name of the runtime library you wish to use - libart.so or libdvm.so. So, you can switch back to Dalvik like so:

adb shell 'echo libdvm.so &gt;/data/property/persist.sys.dalvik.vm.lib'

Source