Veency is the perfect application to view and control the screen of your jailbroken iDevice. Search for Veency on Cydia and download it. Now
see the IP Address of your iDevice by going to -
Settings --> WiFi --> Tap the little Blue icon next next to the name of your wi-fi network --> A screen with all the details will appear --> Your IP address will be on this screen.
Now open Safari.
Click on the URL Bar.
Type in vnc:// and then the IP Address. For example - vnc://192.168.1.2
Your iDevice screen will now open on your computer and you can use the mouse to control it.