Exact same problem here.

Small business, low call volume, and we use mobile phones as your telephone endpoints exclusively.

Currently, it is extremely cumbersome to have to log into the Zendesk dashboard -- which renders on a mobile in a full desktop layout -- just to tap the tiny softphone icon to get a dial screen, etc.

It is a common task to field calls and originate outbound calls from our mobiles, which is exactly why we choose to use this type of service vs. a traditional office-based phone system.

However, the current limitation that there is not a mobile-friendly app or interface on Zendesk results in a lot of frustration -- especially when a competitor service (Freshdesk) already has a mobile support app that has the phone interface built in.