The Lifesize Video mobile app for UVC was released in March 2015. There was no update in the app stores since then.
Most current popular mobile phones like Apple iPhone6, Samsung Galaxy S5, S6, ... are not in the list of supported devices. The app may work, but users get the message "unsupported device" and think better not to use it.
Lifesize should update the mobile apps for UVC to support current mobile phones and tablets.