Mobile business applications (mobile business apps) bear huge potentials for increased work productivity, work comfort, and even sales if they are of high quality. Usability and user experience, in particular, are among the key quality attributes. The high quality requirements of mobile business apps require them to be thoroughly engineered. Unfortunately, today's software engineering approaches are often too heavy-weight to allow developing highquality mobile business apps in the context of mobile projects, which often face small budgets, extremely limited effort, and short time-to-market requirements. This paper presents mConcAppt, a user-centered and lightweight conception method for mobile business apps. It provides guidance for requirements engineering and interaction design for mobile business apps and provides interfaces to other activities, such as visual design, architectural design, implementation, and testing. The adoption of mConcAppt in various industrial contexts indicates that it enables organizations to elaborate a concept for a highquality mobile business app in 2-4 weeks.