Fix HTTP(s) Issues in Kotlin Multiplatform Apps

HTTP(s) issues in KMP apps

HTTP(s) issues are failures in the data exchange between the app and its servers. Most Kotlin Multiplatform (KMP) apps make their API calls from shared code using the Ktor client, which runs on the OkHttp engine on Android and on the Darwin or CIO engine on iOS.

The most common HTTP(s) issues are connection errors, where the app cannot reach the server; status code errors such as 401, 404 or 500; delayed calls, where the response arrives much later than expected; and duplicate calls, where the same request is sent more than once.

Because the networking layer is shared, one broken endpoint or bad request can affect both the Android and iOS apps, but the failure may show up differently on each engine.

Why does this happen?

HTTP(s) issues in KMP apps usually come from:

Connection errors: No network, DNS failures, dropped connections or wrong base URLs in configuration.

Delayed calls: Slow backend endpoints, large payloads, or engine timeouts that differ between Android and iOS.

Authorization errors: Expired or missing tokens, or headers set on one platform but not the other.

Server errors: Backend crashes, misconfiguration or overload returning 5xx responses.

Duplicate calls: Retries, repeated recomposition or multiple collectors of the same flow firing the same request again.

Serialization mismatches: Responses that no longer match the shared data models.

How to fix it using Appxiom

• Locate issue report: The issue report shows the full URL, status code, duration, and request and response headers and body. Sensitive headers can be masked with Observe.setMaskedHeaders.
• Group dynamic endpoints: Use Observe.setUrlPatterns so calls like /users/123 and /users/456 are reported as one endpoint.
• Set it up: Install AppxiomKtorPlugin in your shared HttpClient and, for the iOS Darwin engine, add the AX settings to Info.plist, as described in Network Monitoring for KMP.