8 Steps App Development
You come up with the idea of what you want to build and what features/functionalities you like to have in the app. Create some stories about how your users will use the app.
2. UX Design
Work with the User experience designer to create the layout and flow of the App experience. Its about the structure of your overall app. What will user see when they launch the app ? and how they will navigate in the app to use all the functionalities with ease ? UX designer will create something called Wireframes for you. Wireframe is a document that describes the overall structure of your application without visual details like Color / icons etc.
3. Graphics Design
Once you have UX design done, you can ask graphics designer to work on wireframes and come up with good looking visual design for your app. This is the step where your idea will turn into beautiful looking idea!
(Usually UX designer and Graphics designer could be the same person)
You provide UX and Design documents to the developer who will do programming and turn your idea into a real App.
Once you have the very first version (called beta version) of the app developed , you go out and ask people to test your app and get user feedback. This is very important step to find issues and helpful tips from the users on how to improve your app.
6. Fix Bugs
Once you get the feedback from the early users, go back to your developer and ask him/her to make the changes according to the feedback.
At this point you have the app that looks good, easy to use, functions as expected and approved by the early users. Once you are satisfied with the app, you can go ahead and launch the app in the App Store!
App development is a continuous process of improvement and development. You can go to the step 3 and iterate the entire process again to keep improving the app.