Play Store submission in Android Kotlin - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Understanding the Play Store App Signing

Which statement correctly describes the Play Store app signing process?

A You cannot use Google Play app signing if you want to update your app later.

B You must always sign your app with a debug key before uploading to Play Store.

C Play Store requires you to upload unsigned APKs and signs them automatically.

D Google manages the app signing key and signs your app after upload, improving security.

💡 Hint

Think about who holds the signing key for security and updates.

Google Play app signing means Google holds the signing key and signs your app after you upload an APK or AAB, which enhances security and allows easier key management.

❓ ui_behavior

intermediate

Play Store Listing Requirements

Which of the following is NOT required when submitting an app to the Play Store?

A A minimum of 10 user reviews before publishing

B A high-resolution app icon in PNG format

C A signed APK or AAB file

D A privacy policy URL if your app collects user data

💡 Hint

Consider what Play Store requires before publishing versus what happens after.

User reviews are collected after publishing; they are not required before submission. The other options are mandatory for Play Store submission.

❓ lifecycle

advanced

Versioning and Updates

What will happen if you upload an APK with a lower versionCode than the current Play Store version?

A The Play Store will accept it and replace the current version silently.

B The Play Store will reject the upload with an error about versionCode.

C The Play Store will publish both versions simultaneously.

D The Play Store will automatically increase the versionCode for you.

💡 Hint

Think about how Play Store ensures users get the latest app version.

Play Store requires each new upload to have a higher versionCode than the previous one to prevent downgrades and confusion.

❓ navigation

advanced

Play Store Console Navigation

Where in the Play Console do you upload your app bundle for release?

A Under the 'Release' section, inside 'Production' or other tracks

B In the 'Store Presence' tab under 'Store Listing'

C In the 'User Feedback' section

D In the 'Monetize' tab under 'Pricing & Distribution'

💡 Hint

Uploading the app bundle is part of releasing the app to users.

The 'Release' section is where you manage app versions and upload bundles or APKs for production or testing tracks.

📝 Syntax

expert

Correct Gradle Configuration for Play Store

Which Gradle snippet correctly sets the versionCode and versionName for Play Store submission?

Android Kotlin

android {
    defaultConfig {
        // Fill in the correct versionCode and versionName
    }
}

A

versionCode = 5
versionName = "1.0.4"

B

versionCode "5"
versionName 1.0.4

C

versionCode 5
versionName "1.0.4"

D

versionCode: 5
versionName: "1.0.4"

💡 Hint

Remember Gradle uses a specific syntax without equals or colons here.

In Gradle, versionCode and versionName are set without equals or colons, and versionCode is an integer, versionName is a string.

Practice

1. Why is it important to sign your Android app before submitting it to the Play Store?

easy

A. It verifies the app's author and ensures updates come from the same source.

B. It makes the app run faster on all devices.

C. It automatically translates the app to multiple languages.

D. It removes all bugs from the app.

Solution

1. Step 1: Understand app signing purpose

   Signing confirms the identity of the developer and secures app updates.

2. Step 2: Recognize Play Store requirements

   Google Play requires signed apps to ensure trust and security for users.

3. Final Answer:

   It verifies the app's author and ensures updates come from the same source. -> Option A

4. Quick Check:

   App signing = Verify author and secure updates [OK]

Hint: Signing proves app ownership and update safety [OK]

Common Mistakes:

• Thinking signing improves app speed
• Believing signing translates the app
• Assuming signing fixes bugs automatically

2. Which of the following is the correct way to specify the version code in your Android app's build.gradle file before Play Store submission?

easy

A. versionCode = 1

B. versionCode = "1.0"

C. versionCode = true

D. versionCode = 1.0

Solution

1. Step 1: Identify versionCode data type

   versionCode must be an integer, not a string or decimal.

2. Step 2: Check each option's type

   versionCode = 1 uses an integer 1, which is correct; others use string, boolean, or float.

3. Final Answer:

   versionCode = 1 -> Option A

4. Quick Check:

   versionCode = integer [OK]

Hint: versionCode must be an integer number [OK]

Common Mistakes:

• Using quotes around versionCode value
• Using decimal numbers for versionCode
• Assigning boolean values to versionCode

3. Given this snippet in your build.gradle file, what will happen when you try to upload the app to the Play Store?

android {
    defaultConfig {
        applicationId "com.example.app"
        minSdkVersion 21
        targetSdkVersion 33
        versionCode 2
        versionName "1.1"
    }
}

medium

A. The upload will fail because applicationId is missing.

B. The app will upload successfully with version 1.1 and code 2.

C. The app will upload but with minSdkVersion ignored.

D. The upload will fail because versionCode must be a string.

Solution

1. Step 1: Check versionCode and versionName types

   versionCode is integer 2 and versionName is string "1.1" which is correct.

2. Step 2: Verify required fields

   applicationId, minSdkVersion, targetSdkVersion are all present and valid.

3. Final Answer:

   The app will upload successfully with version 1.1 and code 2. -> Option B

4. Quick Check:

   Valid config = Successful upload [OK]

Hint: Check types and required fields before upload [OK]

Common Mistakes:

• Confusing versionCode type as string
• Missing applicationId in config
• Assuming minSdkVersion is optional

4. You tried to submit your app to the Play Store but got an error saying your APK is not signed. What is the most likely cause?

medium

A. You used the wrong package name in your manifest.

B. Your app's versionName is missing.

C. You forgot to generate and use a signing key before building the APK.

D. You set minSdkVersion too high.

Solution

1. Step 1: Understand the error message

   "APK is not signed" means the app was built without a signing key.

2. Step 2: Identify the cause

   Not generating or applying a signing key before building causes this error.

3. Final Answer:

   You forgot to generate and use a signing key before building the APK. -> Option C

4. Quick Check:

   Unsigned APK error = Missing signing key [OK]

Hint: Unsigned APK error means no signing key used [OK]

Common Mistakes:

• Confusing package name errors with signing errors
• Ignoring versionName warnings
• Thinking minSdkVersion affects signing

5. You want to submit an update to your app on the Play Store. Your current live app has versionCode 5 and versionName "1.4". Which of the following is the correct way to update these values in your build.gradle file?

hard

A. versionCode 5
versionName "1.5"

B. versionCode 6
versionName "1.4"

C. versionCode 4
versionName "1.5"

D. versionCode 6
versionName "1.5"

Solution

1. Step 1: Understand Play Store versioning rules

   versionCode must increase with each update; versionName usually increases to reflect new version.

2. Step 2: Evaluate options

   versionCode 6 versionName "1.5" increases versionCode to 6 and versionName to "1.5", which follows rules.

3. Final Answer:

   versionCode 6 versionName "1.5" -> Option D

4. Quick Check:

   Update requires higher versionCode and updated versionName [OK]

Hint: Always increase versionCode and update versionName for new releases [OK]

Common Mistakes:

• Keeping versionCode same as previous release
• Decreasing versionCode accidentally
• Not updating versionName with new release