The additional revenue that comes from a perfect domain is roughly equivalent to the cost of building a bike shed. Actually, it depends on the audience, as ibs

The additional revenue that comes from a perfect domain is roughly equivalent to the cost of building a bike shed. Actually, it depends on the audience, as ibstudios pointed out. A "mobile audience" isn't enough information to make a good decision; among potential users of mobile devices are such different groups as children, adults who raise children, adults who don't raise children, old people... These groups can be broken into even smaller demographics. If you're counting pennies, more alternative TLDs can be more expensive over time (https://news.ycombinator.com/item?id=7069513 https://news.ycombinator.com/item?id=7069513). If you can find a short but not too cryptic .com, go with it. An .io, for instance, has the advantage of shortness and more available English words. The domain name should be pretty low on the list of priorities for your app. Focus on design (for the app and for marketing pages), content and marketing copy, good customer service, and performance.