Note: Non-nexus 4 users, if your device supports OTG, buy an OTG cable (comes very cheap) connect a standard PC mouse and the device to it and use the mouse to navigate the device.
Since the USB debugging is enabled and authorized, you can make good use of KeyEvents. Use input command to simulate up, down, left, and right navigational turns and enter.
Command:
adb shell input keyevent KEYCODE
Examples:
adb shell input keyevent 22 # navigates one block rightward adb shell input keyevent KEYCODE_DPAD_DOWN # navigates one block downward adb shell input keyevent DPAD_LEFT # navigates one block leftward
Relevant key codes:
19 --> "KEYCODE_DPAD_UP"
20 --> "KEYCODE_DPAD_DOWN" 21 --> "KEYCODE_DPAD_LEFT" 22 --> "KEYCODE_DPAD_RIGHT" 23 --> "KEYCODE_DPAD_CENTER"
(See more key codes here - by Rene Barbosa)
To simulate ENTER, use key code 66. 23 works too.
Use the key codes in combination. For example, when SuperSU app asks me to allow or deny root privileges to an app, I use the key codes 19, 20, 22 and 66 to simulate a tap on OK.