Honestly, the group business chat niche is just riddled with "incomplete" products in my opinion. Some are great in the browser but have no native web apps (Flowdock), some have shitty mobile apps with mediocre web versions (campfire and hipchat).
I hope someone with a good set of developers, cash in their pockets, and an eye on simplicity would come in and build a full suite of desktop and mobile apps on the back of a good chat system one day. It's absolutely not a solved problem at this point.