Ease-of-use and visual impact get top priority.
The "wow factor". A good UI/UX design is how you will differentiate from your competitors. It's how you'll improve your users experience and productivity with your solution.
Every mobile platform is deepening more and more their efforts regarding aesthetics and usability, and no startup nor established business can ignore it. Design is at the core of mobile solutions business nowadays, and it's a top priority for us, too.