Design API contracts for version skew
Mobile clients cannot all update at once. Backend changes must remain compatible with older app versions or use explicit versioning and feature negotiation.
Treat request/response schemas as contracts, use tolerant readers where appropriate and measure client-version distribution before removing old behavior.
Make offline behavior explicit
Offline support is not a boolean feature. Define which actions can be queued, what data is cached, how long it remains valid, how conflicts are resolved and what the user sees during degraded connectivity.
Sync needs identifiers, retry policy, deduplication and conflict semantics. Without these rules, offline mode becomes data corruption with a nicer UI.
Keep authentication and local state secure
Store tokens in platform secure storage, minimize sensitive local data and define logout/revocation behavior. Device compromise, screenshots, backups and rooted devices may matter depending on the product threat model.
Authorization still belongs on the server. Hiding a button in the app is not an access-control boundary.
Instrument product and technical health together
Crash rate is not enough. Track startup time, API failure rate, sync failures, screen latency, battery/network cost and business funnel events.
A release can be technically stable while conversion collapses. Product analytics and engineering telemetry should be viewed together.
Use staged rollout and kill switches
Mobile releases are hard to roll back instantly. Use phased rollout, remote configuration and server-side feature flags so risky capabilities can be disabled without waiting for a new store review.
Release gates should include crash-free users, ANR or hang metrics, backend error deltas and key funnel health.
Test the lifecycle, not only screens
Real failures happen during rotation, backgrounding, process death, permission changes, expired tokens, interrupted uploads and partial sync.
Automated tests should cover state restoration and critical workflows across these lifecycle transitions. Device farms help, but production telemetry remains the final feedback loop.