Error and crash reporting

Latest Dynatrace
Explanation
Published Dec 22, 2025

Monitoring Application Not Responding (ANR) and crashes is critical for ensuring a seamless user experience. These issues can lead to app uninstalls, negative reviews, and loss of user trust. By proactively detecting and addressing these errors, you can improve app stability and retain user engagement.

Dynatrace provides detailed insights into ANR and crash events, including stack traces, session details, and device-specific information to quickly identify root causes and implement fixes.

ANR detection

With the new RUM experience, Dynatrace automatically captures "Application Not Responding" (ANR) errors. ANRs are critical to monitor because they cause frustration to the user. The main problem is that the app's main thread, which is responsible for updating the UI, can't process user input events or draw, causing the app to appear frozen.

On iOS, ANRs are detected when the main thread is blocked for longer than the configured timeout interval (default: 2 seconds). When the main thread becomes unresponsive, OneAgent captures a live stack trace to help identify the root cause of the freeze.

ANR events are reported only if the app restarts after being terminated due to an ANR condition.
ANR detection is automatically disabled when a debugger is attached to avoid false positives during development.

What is captured

For each ANR event, the SDK captures:

Live stack trace at the time of the freeze.
Timestamp of the ANR occurrence.
Session and device context information.

This data can be analyzed in apps such as the Error Inspector, or queried directly in Grail using DQL. For the field reference, see Application Not Responding.

Disable ANR detection

By default, ANR detection is enabled. To disable it, set the DTXANRReportingEnabled configuration key to false in your app's Info.plist:

<key>DTXANRReportingEnabled</key>
<false/>

Configure ANR timeout

The default timeout for detecting an ANR is 2 seconds. You can adjust this value using the DTXANRTimeout configuration key in your Info.plist file. The value is specified in seconds:

<key>DTXANRTimeout</key>
<integer>3</integer>

Limitations

Debugger attached—ANR detection is disabled when a debugger is attached to prevent false positives during development and debugging sessions.

Crash reporting

Dynatrace automatically captures and reports crashes that occur in your iOS application. When the app crashes and is restarted, OneAgent sends the crash report to Dynatrace, including the full stack trace and session context.

Crash reports are sent only when the app is restarted after a crash.
Crash detection is automatically disabled when a debugger is attached to avoid interference during development.

What is captured

For each crash event, the SDK captures:

Exception name and reason.
Signal name and number.
Full crash stack trace.
Session and device context information.
Timestamp of the crash.

This data can be analyzed in apps such as the Error Inspector, or queried directly in Grail using DQL. For the field reference, see Crashes.

Disable crash reporting

By default, crash reporting is enabled. To disable it, set the DTXCrashReportingEnabled configuration key to false in your app's Info.plist file:

<key>DTXCrashReportingEnabled</key>
<false/>

Limitations

Debugger attached—Crash detection is disabled when a debugger is attached. This prevents the crash reporter from interfering with the debugging process.
External crash handlers—If another crash reporting tool handles the crash before OneAgent, the crash may not be reported to Dynatrace. We recommend using only one crash reporting tool at a time.
Symbolication—For human-readable stack traces, upload your app's dSYM files to Dynatrace. Without symbolication, stack traces contain memory addresses instead of function names and line numbers.

We don't recommend using multiple monitoring tools with crash reporting enabled simultaneously. This can cause compatibility issues, incorrect reporting, and loss of crash data.

Configuration summary

Configuration key	Default	Description
`DTXCrashReportingEnabled`	`true`	Enables or disables crash reporting
`DTXANRReportingEnabled`	`true`	Enables or disables ANR detection
`DTXANRTimeout`	`2`	ANR detection timeout in seconds

Symbolication

To get human-readable stack traces in your crash and ANR reports, upload your app's dSYM (debug symbol) files to Dynatrace. Without dSYM files, stack traces contain memory addresses instead of meaningful function names and line numbers.

For instructions on uploading dSYM files, see Mobile symbolication.