To succeed today, with a mobile app or otherwise, you've got to be obsessed with what your customers go through. Call it the user experience, the customer experience, the ideation-info-architectural-construct, whatever: it's that delight-or-plight of your users that you must obsess over.
Sure, you could outsource it to someone else—on the team, or outside. But it won't work. You can't outsource obsession. If the very future of your company depends on delivering a....