Start with the Journey and Its Constraints
Before comparing frameworks, describe the work a person needs to complete. Identify the systems involved, the information the app needs and the points where a person can lose progress. Agree on expected behavior when connectivity drops, an account session expires or a downstream service is unavailable.
Our recommendation is to use a short set of important journeys to evaluate architecture options. A team should be able to explain how each option handles the same conditions. This gives business and engineering leaders something concrete to assess alongside development effort.
Separate Shared Rules from the Platform Experience
Decide where business rules, identity, data definitions and service contracts belong. Then identify the parts of the experience that need to reflect each platform. Sharing an API contract or a product rule does not require every screen to behave identically.
Google's Android architecture recommendations distinguish the UI and data layers and recommend separating their responsibilities. Apple's Human Interface Guidelines emphasize consistency with platform conventions. Together, these provide useful inputs for an architecture review, without deciding which cross-platform approach fits a particular product.
Document what is shared, what remains platform-specific and why. Evaluate native development, shared business logic and shared UI against the product's requirements, team skills and maintenance responsibilities. A higher proportion of shared code is not, by itself, a measure of a better customer experience.
Make the Important Decisions Reviewable
Keep a brief decision record for choices that affect both platforms or several teams. Record the constraint, alternatives, selected approach, owner and conditions that would justify revisiting it. Use a diagram where it makes system boundaries easier to understand.
- Agree on API contracts, error handling and compatibility expectations.
- Identify who owns shared components and who approves changes.
- Define platform-specific accessibility and interaction checks.
- Plan for supported operating-system versions and dependency updates.
Validate a Complete Journey Before Expanding
Build a small, complete journey across the app and its dependent services. Include authentication, loading states, failures and recovery in the review. Use representative devices and accessibility settings to check whether the architectural choice holds up in practice.
Agree on acceptance criteria before expanding the scope. Useful evidence can include observed task completion, responsiveness, failure recovery and maintainability findings. Set thresholds for the product's context rather than adopting a generic performance promise.
Carry Governance into Delivery
Architecture decisions need owners during implementation and after release. Connect the decision record to the backlog, release dependencies and operating responsibilities. Review exceptions when they occur and record the reason for accepting them.
A useful starting deliverable is a mobile architecture brief: priority journeys, shared and platform-specific responsibilities, system dependencies, acceptance criteria and decision owners. It provides a basis for choosing the team and delivery sequence without committing prematurely to a particular framework.
- Evaluate architecture through important customer journeys and their failure conditions.
- Define shared responsibilities while preserving the experience each platform needs.
- Connect architecture decisions to owners, acceptance criteria and delivery work.