Crash reporting in Firebase - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is crash reporting in Firebase?

Crash reporting in Firebase is a service that automatically collects and reports app crashes to help developers find and fix bugs quickly.

beginner

How does Firebase Crashlytics help developers?

Firebase Crashlytics groups similar crashes, shows detailed error logs, and highlights the exact line of code causing the crash, making debugging easier.

intermediate

What is a 'crash-free user' in Firebase Crashlytics?

A crash-free user is someone who uses the app without experiencing any crashes during a session, helping measure app stability.

intermediate

Why is it important to add custom keys and logs in Firebase Crashlytics?

Custom keys and logs provide extra context about app state and user actions before a crash, helping developers understand and fix issues faster.

beginner

What steps are needed to enable Firebase Crashlytics in an app?

To enable Crashlytics: 1) Add Firebase to your app, 2) Add Crashlytics SDK, 3) Initialize Crashlytics in code, 4) Build and run the app to send crash reports.

What does Firebase Crashlytics primarily do?

A Manages user authentication

B Collects and reports app crashes automatically

C Improves app performance by caching data

D Hosts app backend services

Firebase Crashlytics automatically collects crash reports to help developers fix bugs.

Which of these helps provide extra context before a crash in Crashlytics?

A Custom keys and logs

B User authentication tokens

C Database backups

D App store ratings

Custom keys and logs add useful information about app state before a crash.

What is the first step to enable Crashlytics in your app?

A Create a database schema

B Write custom crash handlers

C Deploy app to production

D Add Firebase to your app project

You must first add Firebase to your app before using Crashlytics.

How does Crashlytics group crash reports?

A By similar error types and stack traces

B By user location

C By app version only

D By device battery level

Crashlytics groups crashes by similar errors and stack traces to simplify debugging.

What does a 'crash-free user' indicate?

A User who uninstalled the app

B User who reported a crash manually

C User who did not experience any app crashes

D User who updated the app recently

A crash-free user is one who uses the app without crashes during their session.

Explain how Firebase Crashlytics helps improve app quality.

Think about how crash data helps developers understand problems.

Describe the basic steps to set up Firebase Crashlytics in a mobile app.

Focus on setup order from Firebase integration to running the app.

Practice

1. What is the main purpose of Firebase Crashlytics in an app?

easy

A. To store user data securely

B. To manage user authentication

C. To improve app loading speed

D. To automatically collect and report app crashes

Solution

1. Step 1: Understand Crashlytics role

   Firebase Crashlytics is designed to track and report app crashes automatically.

2. Step 2: Compare with other options

   Storing user data, improving speed, and managing authentication are not Crashlytics functions.

3. Final Answer:

   To automatically collect and report app crashes -> Option D

4. Quick Check:

   Crashlytics = crash reporting [OK]

Hint: Crashlytics = crash reports, not data or speed [OK]

Common Mistakes:

• Confusing Crashlytics with user data storage
• Thinking it speeds up the app
• Mixing it with authentication services

2. Which Firebase Crashlytics method is used to log custom messages before a crash?

easy

A. crashlytics.sendReport()

B. crashlytics.recordError()

C. crashlytics.log()

D. crashlytics.startSession()

Solution

1. Step 1: Identify logging method

   The method to add custom logs before a crash is crashlytics.log().

2. Step 2: Understand other methods

   recordError() reports errors, sendReport() and startSession() are not valid Crashlytics methods.

3. Final Answer:

   crashlytics.log() -> Option C

4. Quick Check:

   Logging = crashlytics.log() [OK]

Hint: Use .log() to add messages before crash [OK]

Common Mistakes:

• Using recordError() to log messages
• Assuming sendReport() exists
• Confusing startSession() with logging

3. Given this code snippet, what will Crashlytics report?

try {
  throw new Error('Test crash');
} catch (e) {
  firebase.crashlytics().recordError(e);
}

medium

A. Crashlytics reports a non-fatal error with message 'Test crash'

B. Crashlytics logs a warning but no error

C. App crashes immediately without reporting

D. No crash reported because error is caught

Solution

1. Step 1: Analyze try-catch behavior

   The error is thrown but caught, so the app does not crash.

2. Step 2: Understand recordError effect

   recordError() sends a non-fatal error report to Crashlytics with the error message.

3. Final Answer:

   Crashlytics reports a non-fatal error with message 'Test crash' -> Option A

4. Quick Check:

   recordError() = non-fatal error report [OK]

Hint: recordError() reports caught errors as non-fatal [OK]

Common Mistakes:

• Thinking caught errors cause app crash
• Assuming no report if error is caught
• Confusing recordError() with crash trigger

4. You added firebase.crashlytics().log('User clicked button'); but no logs appear in Crashlytics dashboard. What is the likely issue?

medium

A. Logs only appear after a crash occurs

B. log() method does not exist in Crashlytics

C. Crashlytics SDK is not initialized properly

D. You must call sendReport() to send logs

Solution

1. Step 1: Check Crashlytics log behavior

   Logs sent by log() appear only when a crash happens afterward.

2. Step 2: Verify other options

   SDK initialization is required but if logs never appear, it's likely due to no crash. log() exists and sendReport() is not a Crashlytics method.

3. Final Answer:

   Logs only appear after a crash occurs -> Option A

4. Quick Check:

   Logs show after crash [OK]

Hint: Logs appear only after crash triggers [OK]

Common Mistakes:

• Assuming logs show immediately
• Thinking log() method is missing
• Trying to send logs manually

5. How can you ensure that a caught error with extra context is reported to Firebase Crashlytics as a non-fatal issue with custom keys?

hard

A. Only use crashlytics().log() with error message

B. Use crashlytics().setCustomKey() before recordError()

C. Throw the error again to trigger a crash

D. Call crashlytics().sendReport() after catching error

Solution

1. Step 1: Add context with custom keys

   Use setCustomKey() to add extra info about the error context.

2. Step 2: Report error as non-fatal

   Call recordError() to send the caught error along with custom keys to Crashlytics.

3. Final Answer:

   Use crashlytics().setCustomKey() before recordError() -> Option B

4. Quick Check:

   Custom keys + recordError() = detailed non-fatal report [OK]

Hint: Set keys before recordError() for context [OK]

Common Mistakes:

• Only logging message without keys
• Throwing error again causes crash
• Using non-existent sendReport() method