If you build it, congratulations, but don’t expect too much. If you build it, market it, support it, monitor its publicity, and keep improving it, then they will come, slowly, in fives and tens. Each new subscription is proof that you’re getting somewhere. The trick is ensuring constant growth, and that takes hard work.
Finding the right price points, attracting your target market, writing a blog they read, speaking at events they attend, supporting your current customer-base 24/7, adding features as you see fit, all of this is hard work. It’s usually a lot harder than the programming challenges.
You have to assume that anything you’re putting out there will have some success. Success typically means a number of paying customers, who you must support and communicate with. It’s not just writing an app, it’s attracting a market, supporting customers, dealing with enquiries, writing blog posts, talking to technology news sites, partnering with complimentary applications, handling feature requests. All of that is hard, but you have to plan for it if you’re assuming success, and if you’re not assuming success then what are you doing?