Activate Device Administrator via ADB Is it possible to activate Device Administrator via ADB command instead of tapping 

"Setting -> Security -> Device Administrators --> Select App --> Activate"

on handheld?

If it's possible, how?
It's not possible. The settings code is specifically written to prevent this. The closest  you can come is to bring up the Device Administration Settings page in the Settings app. You can do this with:
adb shell am start -S &quot;com.android.settings/.Settings\$DeviceAdminSettingsActivity&quot;