Analytics and Crashlytics in iOS Swift - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the main purpose of Analytics in a mobile app?

Analytics helps track user behavior and app usage to understand how users interact with the app and improve it.

beginner

What does Crashlytics do in an iOS app?

Crashlytics automatically reports app crashes and errors, helping developers find and fix bugs quickly.

intermediate

How do you log a custom event in Firebase Analytics using Swift?

Use Analytics.logEvent with the event name and parameters, for example: Analytics.logEvent("button_click", parameters: ["button_name": "play"]).

intermediate

Why is it important to add user identifiers in Crashlytics?

Adding user identifiers helps link crash reports to specific users, making it easier to reproduce and fix issues.

beginner

What is a common first step to integrate Firebase Analytics and Crashlytics in an iOS app?

Add Firebase to the project using CocoaPods or Swift Package Manager and configure it in AppDelegate or the main app file.

Which Firebase service helps you track app crashes?

A Realtime Database

B Crashlytics

C Cloud Firestore

D Authentication

Crashlytics is the Firebase service designed to report app crashes and errors.

What method is used to log events in Firebase Analytics for iOS?

A Analytics.logEvent

B Crashlytics.logEvent

C Firebase.logEvent

D EventTracker.log

Analytics.logEvent is the correct method to log custom events in Firebase Analytics.

Why should you avoid logging sensitive user data in Analytics?

A It makes the app UI slower

B It improves app speed

C It increases crash reports

D It can violate user privacy and policies

Logging sensitive data can violate privacy laws and Firebase policies.

Where do you typically initialize Firebase in an iOS app?

A In the Info.plist file

B In the storyboard

C In AppDelegate or main app file

D In the LaunchScreen

Firebase is usually initialized in AppDelegate or the main app entry point.

What does Crashlytics provide besides crash reports?

A Non-fatal error logging

B User interface design

C Database management

D Authentication services

Crashlytics can log non-fatal errors to help diagnose issues that don't crash the app.

Explain how Firebase Analytics and Crashlytics work together to improve an iOS app.

Think about how understanding users and fixing crashes can make the app better.

Describe the steps to add Firebase Analytics and Crashlytics to a new iOS project.

Start from adding the library to your project and end with testing.

Practice

1. What is the main purpose of using Analytics in an iOS app?

easy

A. To track user actions and app usage patterns

B. To report app crashes and errors

C. To improve app performance by optimizing code

D. To manage app permissions and privacy settings

Solution

1. Step 1: Understand Analytics role

   Analytics collects data about how users interact with the app, like button taps or screen views.

2. Step 2: Differentiate from Crashlytics

   Crashlytics focuses on crash reports, not user behavior tracking.

3. Final Answer:

   To track user actions and app usage patterns -> Option A

4. Quick Check:

   Analytics = user action tracking [OK]

Hint: Analytics tracks usage; Crashlytics tracks crashes [OK]

Common Mistakes:

• Confusing Analytics with Crashlytics
• Thinking Analytics fixes crashes
• Assuming Analytics manages permissions

2. Which Swift code snippet correctly logs a custom event named "purchase_complete" using Firebase Analytics?

easy

A. Analytics.logEvent("purchase_complete", parameters: [:])

B. Analytics.logEvent(purchase_complete, parameters: [:])

C. Analytics.logEvent("purchase_complete", parameters: "nil")

D. Analytics.logEvent('purchase_complete')

Solution

1. Step 1: Check method signature

   The correct method requires event name as a string and parameters as a dictionary (can be empty).

2. Step 2: Validate syntax correctness

   Analytics.logEvent("purchase_complete", parameters: [:]) uses a string event name and an empty dictionary, matching the required syntax.

3. Final Answer:

   Analytics.logEvent("purchase_complete", parameters: [:]) -> Option A

4. Quick Check:

   Correct syntax = Analytics.logEvent("purchase_complete", parameters: [:]) [OK]

Hint: Event name as string, parameters as dictionary [OK]

Common Mistakes:

• Missing quotes around event name
• Passing nil instead of dictionary
• Omitting parameters argument

3. Given the following Swift code snippet using Crashlytics, what will happen when a crash occurs?

Crashlytics.crashlytics().log("User tapped buy button")
fatalError("Simulated crash")

medium

A. The app crashes but the log message is lost

B. The log message causes a runtime error

C. The app does not crash because log prevents it

D. The log message is sent to Crashlytics before the app crashes

Solution

1. Step 1: Understand Crashlytics log behavior

   Calling log records a message that is sent to Crashlytics on next app launch after a crash.

2. Step 2: Analyze crash trigger

   fatalError causes an immediate crash, but the log message is preserved for reporting.

3. Final Answer:

   The log message is sent to Crashlytics before the app crashes -> Option D

4. Quick Check:

   Crashlytics logs persist through crash [OK]

Hint: Crashlytics logs survive crashes for later reporting [OK]

Common Mistakes:

• Assuming logs are lost on crash
• Thinking log prevents crash
• Confusing log with error throwing

4. You added Crashlytics to your app but crash reports are not showing up in the Firebase console. Which of these is the most likely cause?

medium

A. You used fatalError instead of assert

B. You forgot to call Crashlytics.crashlytics().setCrashlyticsCollectionEnabled(true)

C. You did not import UIKit in your Swift file

D. You called Analytics.logEvent instead of Crashlytics methods

Solution

1. Step 1: Check Crashlytics setup requirements

   Crashlytics requires enabling data collection explicitly or via Info.plist to send crash reports.

2. Step 2: Identify missing configuration

   Not calling setCrashlyticsCollectionEnabled(true) disables crash report sending.

3. Final Answer:

   You forgot to call Crashlytics.crashlytics().setCrashlyticsCollectionEnabled(true) -> Option B

4. Quick Check:

   Enable collection to send crash reports [OK]

Hint: Enable Crashlytics collection to receive reports [OK]

Common Mistakes:

• Confusing Analytics logging with Crashlytics setup
• Missing import statements
• Thinking crash method choice affects reporting

5. You want to log a user property "user_level" with value "gold" in Firebase Analytics and also log a non-fatal error in Crashlytics when a payment fails. Which Swift code snippet correctly does both?

hard

A. Analytics.setUserProperty("user_level", forName: "gold")
Crashlytics.crashlytics().record(error: Error("Payment failed"))

B. Analytics.logEvent("user_level", parameters: ["gold"])
Crashlytics.crashlytics().log("Payment failed")

C. Analytics.setUserProperty("gold", forName: "user_level")
Crashlytics.crashlytics().record(error: NSError(domain: "Payment", code: 1, userInfo: nil))

D. Analytics.setUserProperty("gold", forName: "user_level")
Crashlytics.crashlytics().log("Payment failed")

Solution

1. Step 1: Set user property correctly

   Use setUserProperty(_:forName:) with value first, then property name.

2. Step 2: Log non-fatal error properly

   Use record(error:) with an NSError instance to report non-fatal errors.

3. Final Answer:

   Analytics.setUserProperty("gold", forName: "user_level") Crashlytics.crashlytics().record(error: NSError(domain: "Payment", code: 1, userInfo: nil)) -> Option C

4. Quick Check:

   User property + non-fatal error = Analytics.setUserProperty("gold", forName: "user_level") Crashlytics.crashlytics().record(error: NSError(domain: "Payment", code: 1, userInfo: nil)) [OK]

Hint: User property value first, use record(error:) for non-fatal errors [OK]

Common Mistakes:

• Swapping user property name and value
• Using log() instead of record(error:) for errors
• Passing wrong types to methods