Creating an application for the phone (android, iOS)

I need a phone app. As an example, you can see the application of this company. पाठ छिपा हुआ

The application should be implemented payment by Internet banking and credit card. Make it easy, convenient and fast for the client. As for the time, I would like to hear from you. What a real time it can take to develop. The rest of the questions will be discussed in person.