No, you cannot delete the Cydia icon off of the springboard. Instead of deleting the Cydia icon, you should just hide it.  You can hide the Cydia icon and Smartphone icon directly from the Mobile Spy interface. Here's the page on our website that explains the process:

http://www.mobile-spy.com/iphone3.html

The section about hiding the icons is #7 under Accessing & configuring the interface (towards the very bottom of the page).