It's an interesting point. Does a slick app equal a great customer experience? I would say it probably does but only if the app does what it is supposed to do or what the consumer hopes it will do. With an app blizzard it needs to engage with and involve the consumer very quickly if it is to be successful. If it also needs a good signal then frustration could be the experience, which is not even the apps fault.
"It was nice to be in Cannes celebrating slick, but most people are much more driven by quality of experience, of which slickness is a small portion."