A mobile team wants a GraphQL API with real-time subscriptions over WebSockets and built-in offline data sync. Which service is designed for this?
A.Amazon API Gateway REST API
REST API Gateway doesn't serve GraphQL or managed offline sync.
B.AWS AppSync
Correct. GraphQL + subscriptions + sync is AppSync's purpose.
C.Application Load Balancer
ALB is a load balancer, not a managed API layer.
D.Amazon EventBridge
EventBridge routes events between services — not a client-facing GraphQL API.
Why this answer
AppSync is the managed GraphQL service — queries, mutations, and real-time subscriptions over WebSockets, plus offline sync via Amplify DataStore. API Gateway serves REST/HTTP/WebSocket APIs but doesn't provide GraphQL resolvers or data sync out of the box.
Correct answer: B · Last reviewed 2026-10-26
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