Please see the links below for guides from ISC for the soft client (app) on both mobile and desktop platforms, as well as the direct download URLs for both Android and iOS.
Mobile app guide: https://www.isc.upenn.edu/sites/default/files/vonage_mobile_app_with_webex_mobile_quick_start_guide.pdf
Desktop app guide: https://www.isc.upenn.edu/sites/default/files/vonage_mobile_app_softphone_v1_0.pdf
Download links for the mobile app can be found at:
Android: https://play.google.com/store/apps/details?id=com.cisco.wx2.android
iOS: https://apps.apple.com/us/app/cisco-spark/id833967564
Important to note: The soft clients are subject to the Penn WebLogin 30 day auto-logout policy. More information can be found in this support article from CHAS.
If you require further assistance after going through this knowledge article, please submit a ticket at support.collegehouses.upenn.edu.