Precisely define your idea
Get a sheet of paper and try to write down all most important information about your app - main features (in other words: what your potential user can do in your app), potential clients (your target group), how do you want to monetize it and try to find your competitive advantage.
Find a mentor
Choose a software house, which will help you to develop your idea into business, choose appropriate platforms to launch it on and then verify features of the application with your vendor and potential clients. This part is most important!
Alongside with your vendor try to decide how exactly your application should look. Good software house should prepare a pack of views waiting for your acceptation.
Make a prototype
That’s where the implementation process starts - integration with API (if necessary), staging environmentss, and a lot more of technical stuff you shouldn’t worry about - your software house will be there for you. In the end, you will get the alpha version of your app, so you can test it.
Give it a life
After successfully going through the testing phase, with the help of your vendor let your app conquer App Store and/or Google Play. Be patient, sometime it might take a while before app becomes popular.
Promotion and app maintenance
Promote your app and don’t forget, good software house will stay with you a long time after release, fixing bugs, improving your product and reaching clients.