Mobile app development is a complicated thing. So, if you want to clearly convey your idea to developers and designers you should firstly think through all the details by yourself.
The steps described below influence the final development cost of your product that, in turn, is a great part of your total mobile app development budget.

1. Define for what purpose you need an app

There are lots of scenarios when it comes to the purpose of creating an app. Let’s consider the most common of them. So, you want to create your own app to:
Broaden your opportunities
You have a brand that is present physically or even in a form of e-commerce website but you want to provide your customers with a mobile-friendly experience and get more sales. Such companies as AsosLushWalmart were guided by this scenario. The reason for movement in the direction of mobile commerce is that the number of mobile users is growing rapidly as well as an average bill they spend compared to desktops.
Build your idea
You have a million-worth idea but you have no clue about all that development stuff. You can hire an IT company outsourcing to help you. There are a variety of success stories of companies that outsourced development to implement their products. For example, $3 billion-worth Slack company used outsourcing to build their product in its earliest stages. Opera relied on developers from different countries to create its platform. Another example is Skype whose creators hired a team of developers from Estonia to build their business.
Withstand competition
It is difficult to find a business where mobile solutions would be inappropriate or useless. On the landscape of tough competition, companies that use advantages of mobile apps can dominate over others. So, this scenario is about entrepreneurs who do not want to lose opportunities and leg behind competitors. Taco Bell’s app is an example of this scenario.
Engage your customers
You want to build an engagement platform for your customers like it did Nike with its Nike+ running app. They did not just build a useful product for their target audience but got an opportunity to promote their brand in digital spaces as well.
Depending on a scenario your product’s features as well as its marketing strategy can vary a lot. In turn, it affects time and approach required for UI/UX design, development, and marketing.
As you know, time is money. So, the more time is required for product creation, the larger budget to develop an app you will need.