Android Development Android Performance Optimization 3

Question 1

What does APK size optimization technique 'code shrinking' do via R8 or ProGuard?

Accepted Answer

Removes unused classes, fields, methods, and attributes from the compiled output

Answer

Compresses image assets into WebP format

Answer

Reduces the number of Activities in the manifest

Answer

Splits the APK by screen density

Question 2

What is the purpose of Android App Bundles (.aab) compared to traditional APKs?

Accepted Answer

They let Google Play deliver only the resources and code needed for a specific device

Answer

They allow apps to run without installation

Answer

They combine multiple apps into a single download

Answer

They enable apps to be distributed outside the Play Store

Question 3

Which Android image format is preferred for app assets because it offers superior lossless and lossy compression compared to PNG and JPEG?

Accepted Answer

WebP

Answer

SVG

Answer

BMP

Answer

TIFF

Question 4

What is the role of the 'launch profiling' feature in Android Studio's CPU Profiler?

Accepted Answer

It records CPU activity from the very beginning of app startup to diagnose slow launches

Answer

It simulates low-end device CPU speeds

Answer

It tracks background service CPU usage

Answer

It profiles GPU shader compilation

Question 5

When using DiffUtil with RecyclerView, what is the main performance advantage over calling notifyDataSetChanged()?

Accepted Answer

It calculates the minimal set of changes and animates only affected items

Answer

It prevents the RecyclerView from scrolling during updates

Answer

It batches all updates into a single transaction

Answer

It moves list operations to a background thread automatically

Question 6

What does the Android vitals metric 'ANR rate' measure?

Accepted Answer

The percentage of daily active users who experienced an Application Not Responding dialog

Answer

The percentage of sessions with network request failures

Answer

The average number of crashes per session

Answer

The rate at which background processes are killed by the OS

Question 7

Which approach minimizes object allocation in performance-critical Android code to reduce garbage collection pauses?

Accepted Answer

Use StringBuilder instead of String concatenation in tight loops

Answer

Always use ArrayList over arrays

Answer

Increase the app's maximum heap size

Answer

Disable hardware acceleration for frequently-redrawn views