The lowest-cost useful starting point is usually a narrow first release that supports one complete task. A prototype or browser-based pilot may answer an early question before mobile development. Shared iOS and Android code can reduce duplicated work where suitable, while essential testing, data protection and support still need a budget.
Controlling the budget for a first mobile app release
Start with the smallest version that lets someone complete the promised task. For a booking app, availability and confirmation may matter before loyalty rewards or advanced reports. Keep useful existing tools where they fit and assess integrations before committing to replacement work.
Planning your mobile app project
Identify the one journey you want to test and list features that can wait. Compare a prototype, a browser pilot and a mobile MVP against the uncertainty you need to resolve.