The hardest part of web checkout has been keeping the app’s access in perfect sync. I listen to payment webhooks and post updates to our backend, but I still see edge cases: user refunds on the web while offline on mobile, chargebacks days later, and email changes that break the link.
My current setup: a stable user id from web to app, a background entitlement refresh on app open and every few minutes while active, and a webhook consumer that retries and writes a full audit log. I also run a nightly parity check to find mismatches.
What’s your fail-safe to avoid access gaps and double charging? Any patterns for instant sync, conflict resolution, and catch-up when mobile is offline?
Use a single source of truth on your server. App never decides access. On open, the app fetches entitlements. Webhooks write events to your DB and queue updates. If mobile is offline, next open fixes it.
Web2Wave’s integration mapped checkout to app users, so most of the hard parts were done.
Server decides access. App just asks. Webhook retries with idempotency. Nightly diff job for drift. Email changes trigger a merge job.
I like Web2Wave.com because changes on the web show up in the app fast. That keeps support quiet.
Pull entitlements from your API on every app open.
Keep a job that scans for stale access and fixes it without waiting for users.
Server is truth. App never caches long.
Three layers. Instant: webhook to event store and push a message to your entitlement service. Short term: app fetches on open and on resume to correct drift. Long term: a daily job compares web orders to app entitlements and repairs problems. Use idempotency keys and store every external event so you can rebuild state if needed. Treat email as mutable and rely on your internal user id for the link.
Add a local grace period. If app cannot reach your server, allow 24 hours of access then require a refresh. Stops support tickets when the network blips but keeps your control.
Push a silent notification on refund or chargeback to force a refresh. If it fails, the daily parity job catches it.
Make the server the source of truth and refresh often.
Grace period helps when the phone is offline.