Don’t worry about people stealing an idea. If it’s original, you will have to ram it down their throats.
As quoted, without citation, in Robert Slater, Portraits in Silicon (1987), 88. In reply to a student expressing concern that his own ideas might be stolen before he had published his own thesis.
— Howard Hathaway Aiken
So you have an app idea and you are ready to build it. Hold up, that’s not the next step.
First, do a wireframe mockup of your idea. Find someone in a marketplace (upwork.com or something like it) to make a useable wireframe. Schedule some meetings with your potential customers but don’t use family and friends, put the time into finding your customers. Have those customers click through your wireframe. Get their feedback. Ask them questions as they do it. Write down their answers. Decide whether you are solving one of their problems or if they are in awe of your intelligence because you are building an app. Decide what you want to spend to build a working prototype for iOS. Regardless of what you hear, hold off on Android until you know if the idea is worth the trouble. If you decide to build it. Great! Execution matters here. If your budget is $800 (no idea what your budget is) make sure that you write all of the requirements for how the app should function: Click this, make this happen and drive engagement (notifications, badges, etc), Analytics to know what’s happening (crashes, installs, engagement to your app store landing page) 500,000 people visit your app page and 3 installs? You should know that. Lastly, ad-supported apps with less than 100,000 installs aren’t making a lot of money so think about how you monetize it.
Then be prepared to spend a crazy amount of time understanding how to make money that isn’t a passive income of $50 a month. I have two apps in my niche and the damn things have done very well. Interested parties contact us regularly which is great for those off-app revenue opportunities. I got lucky but it was because I worked on a fairly successful web app in my niche for 5 years before we released our first app.
I sound like an asshole but I don’t mean to, it’s hard, and I learn something new every day, but it’s fun and I make a little money. Leave a comment if I can help you in any way.
2022 Update: Everything I said above is still accurate but I thought I would add the following. IAP or In App Purchases is a viable way to list your app in the stores for free and charge for more/exclusive paid content. This is a decision I am now trying to address in order to prevent a paid app from securing a user. There’s also the thought that recurring monthly revenue is better than a one-time purchase.