Play Store submission in Android Kotlin - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define the app version in the build.gradle file.

Android Kotlin

android {
    defaultConfig {
        versionCode [1]
    }
}

Drag options to blanks, or click blank then click option'

A1

B"1"

CversionCode

DversionName

Attempts:

3 left

💡 Hint

Common Mistakes

Putting quotes around the versionCode number

Using versionName instead of versionCode

The versionCode must be an integer without quotes to specify the app version number.

2fill in blank

medium

Complete the code to sign the APK with the release key in build.gradle.

Android Kotlin

signingConfigs {
    release {
        storeFile file("[1]")
    }
}

Drag options to blanks, or click blank then click option'

Adebug.keystore

Brelease-key.jks

Capp.keystore

Dmy-release-key.keystore

Attempts:

3 left

💡 Hint

Common Mistakes

Using debug.keystore instead of release keystore

Wrong file extension

The storeFile should point to your release keystore file, commonly named my-release-key.keystore.

3fill in blank

hard

Fix the error in the AndroidManifest.xml to set the app's package name.

Android Kotlin

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="[1]">
</manifest>

Drag options to blanks, or click blank then click option'

Acom.example.myapp

BMyApp

Ccom.example

Dexample.myapp

Attempts:

3 left

💡 Hint

Common Mistakes

Using short names like 'MyApp'

Missing domain parts in package name

The package name must be a full domain-style identifier like com.example.myapp.

4fill in blank

hard

Fill both blanks to define the release build type with signing config.

Android Kotlin

buildTypes {
    release {
        minifyEnabled [1]
        signingConfig [2]
    }
}

Drag options to blanks, or click blank then click option'

Afalse

BsigningConfigs.release

Ctrue

DsigningConfigs.debug

Attempts:

3 left

💡 Hint

Common Mistakes

Using signingConfigs.debug for release

Setting minifyEnabled to a string

For release builds, minifyEnabled is often set to false initially, and signingConfig must point to the release signing config.

5fill in blank

hard

Fill all three blanks to create a Play Store listing with title, short description, and full description.

Android Kotlin

playStoreListing {
    title = "[1]"
    shortDescription = "[2]"
    fullDescription = "[3]"
}

Drag options to blanks, or click blank then click option'

AMy Cool App

BAn app that does cool things

CThis app helps you do many cool things easily and quickly.

DCool App

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing title and descriptions

Using too short or unclear descriptions

The title is the app name, the short description is a brief summary, and the full description explains the app in detail for the Play Store listing.

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