[potatolicious]

I don't think it's about the supporting functionality. The caliber your app must be is a function of competition and commoditization.

Just like in the old desktop-PC software days, if you solve a problem important to your customers, and you're the only one around doing it, your software can be as bad and low quality as you want. You're the only game in town for people who need this particular problem solved.

If you however are providing a commodity product in a market filled with competitors, the "quality" of your app (in all the ways we measure quality: stability, responsiveness, design, aesthetics) matters a great deal.

So yeah, if you can own a niche you can get away with some pretty low-caliber development (see: Grubhub's app), but this tends to be temporary. Profitable niches find competitors quickly (see: Seamless, whose mobile app makes Grubhub's look like a child's crayon drawings, and who in the end won and bought Grubhub).