As a student at the University of Zurich, the mobility program provides you with the opportunity to also study at another university in Switzerland. There is little administration involved as you remain matriculated at the University of Zurich and pay your tuition fees here. All information herewith is listed in the "Application & Admission" section:

Swiss-wide Mobility CH-Unimobil
Other Mobility Options

Studying at More than One University (Module Mobility)
Mobility in a Minor Study Program
Joint Degree Mobility
CH-Unimobil