What does the app help people do?
Begin with the tasks and frequency of use. Map-based rentals, booking, news feeds and sports scores each need different navigation patterns.
Consider device capabilities early
If the product needs location, camera, notifications or offline behaviour, permissions and failure scenarios belong in the design phase.
Design the API and the app together
The mobile client, authentication and administrative backend need a shared understanding of data and errors. What happens without a network connection is part of that design.
Do not leave store release until the end
Store descriptions, screenshots, privacy disclosures and versioning are most manageable when planned alongside testing.
