Deep links in Android Kotlin - Build, Publish & Deploy

Build & Publish - Deep links

Performance Impact of Deep Links

Deep links allow users to open specific screens directly, improving user experience by reducing navigation steps. They have minimal impact on frame rate and memory since they mainly affect app launch and navigation logic. However, improper handling can cause delays during app startup if heavy processing occurs when resolving the link.

Battery usage is generally unaffected unless deep link processing triggers background tasks or network calls immediately.

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Optimizing Deep Links for Smooth 60fps Rendering

To keep UI smooth, handle deep link parsing quickly on a background thread. Avoid blocking the main thread during link resolution. Defer heavy data loading until after the initial screen renders.

Use Android Jetpack Navigation component to manage deep link destinations efficiently. Cache any required data beforehand if possible to reduce load time.

Impact on App Bundle Size and Startup Time

Adding deep link support requires minimal additional code and metadata in the AndroidManifest.xml, so the impact on app size is negligible (a few KB).

Startup time can increase if deep link handling triggers complex logic or network requests synchronously. Keep deep link processing lightweight to avoid slowing app launch.

iOS vs Android Differences for Deep Links

On Android, deep links are declared in the manifest and handled via intents. Android supports both http(s) URLs and custom schemes.

iOS uses Universal Links (HTTP URLs associated with the app) and custom URL schemes. Universal Links require hosting an Apple App Site Association file on your website.

Android allows multiple apps to handle the same deep link, prompting the user to choose, while iOS routes Universal Links directly to the app if installed.

Store Review Guidelines and Requirements

• Google Play: Ensure deep links do not lead to inappropriate content or violate policies. The app must handle links securely to prevent phishing or spoofing.
• Apple App Store: Universal Links must be properly configured with valid SSL certificates and association files. Avoid broken links or crashes when handling deep links.
• Both stores require that deep links do not degrade user privacy or security.

Self-Check: Your app takes 5 seconds to load this screen. What's likely wrong?

Deep link handling is probably blocking the main thread with heavy processing or network calls. This delays UI rendering and causes slow startup.

To fix, move deep link parsing and data fetching to background threads and show a loading indicator if needed.

Key Result

Deep links improve user navigation with minimal performance and size impact if handled asynchronously. Proper platform-specific setup and lightweight processing ensure smooth app launch and compliance with store policies.

Practice

1. What is the main purpose of a deep link in an Android app?

easy

A. To open a specific screen inside the app from an external URL

B. To update the app's user interface colors

C. To increase the app's memory usage

D. To change the app's icon on the home screen

Solution

1. Step 1: Understand deep link functionality

   Deep links allow an app to open a specific screen or content when a user clicks a URL outside the app.

2. Step 2: Compare options with this purpose

   Only To open a specific screen inside the app from an external URL describes opening a specific screen from an external URL, which matches deep link behavior.

3. Final Answer:

   To open a specific screen inside the app from an external URL -> Option A

4. Quick Check:

   Deep link purpose = open specific screen [OK]

Hint: Deep links open app screens from outside links [OK]

Common Mistakes:

• Confusing deep links with UI styling
• Thinking deep links change app icons
• Assuming deep links increase memory

2. Which XML element is used to declare a deep link in AndroidManifest.xml?

easy

A. <provider>

B.

C. <service>

D. <activity>

Solution

1. Step 1: Identify where deep links are declared

   Deep links are declared inside an element within an activity in AndroidManifest.xml.

2. Step 2: Match options to this element

   Only is used to specify deep link URL patterns and actions.

3. Final Answer:

   <intent-filter> -> Option B

4. Quick Check:

   Deep links declared in intent-filter [OK]

Hint: Deep links go inside intent-filter tags [OK]

Common Mistakes:

• Confusing activity tag with deep link declaration
• Using service or provider tags incorrectly
• Not nesting intent-filter inside activity

3. Given this intent filter snippet in AndroidManifest.xml, what URL will open the app's activity?

<intent-filter>
  <action android:name="android.intent.action.VIEW" />
  <category android:name="android.intent.category.DEFAULT" />
  <category android:name="android.intent.category.BROWSABLE" />
  <data android:scheme="https" android:host="example.com" android:pathPrefix="/profile" />
</intent-filter>

medium

A. https://example.com/about

B. http://example.com/profile

C. https://example.com/profile/settings

D. https://example.org/profile

Solution

1. Step 1: Analyze the intent filter data attributes

   The scheme is https, host is example.com, and pathPrefix is /profile, so URLs starting with https://example.com/profile will match.

2. Step 2: Check each option against these rules

   https://example.com/profile/settings matches https scheme, example.com host, and path starting with /profile. Options B (http scheme), C (wrong path), and D (wrong host) do not match.

3. Final Answer:

   https://example.com/profile/settings -> Option C

4. Quick Check:

   Match scheme, host, pathPrefix = https://example.com/profile/settings [OK]

Hint: Match scheme, host, and pathPrefix exactly [OK]

Common Mistakes:

• Ignoring scheme (http vs https)
• Confusing host names
• Not checking pathPrefix carefully

4. What is wrong with this intent filter for a deep link?

<intent-filter>
  <action android:name="android.intent.action.VIEW" />
  <category android:name="android.intent.category.LAUNCHER" />
  <data android:scheme="myapp" />
</intent-filter>

medium

A. It uses LAUNCHER category instead of BROWSABLE

B. It is missing the action VIEW

C. The scheme attribute is invalid

D. It should be inside a service tag

Solution

1. Step 1: Check required categories for deep links

   Deep links require the BROWSABLE category to allow opening from browsers or external apps.

2. Step 2: Identify incorrect category usage

   This intent filter uses LAUNCHER category, which is for app launchers, not deep links.

3. Final Answer:

   It uses LAUNCHER category instead of BROWSABLE -> Option A

4. Quick Check:

   Deep links need BROWSABLE category [OK]

Hint: Deep links need BROWSABLE, not LAUNCHER category [OK]

Common Mistakes:

• Using LAUNCHER category for deep links
• Forgetting to add BROWSABLE category
• Placing intent-filter inside wrong tag

5. You want your app to open a user profile screen when a link like myapp://user/123 is clicked. Which intent filter correctly handles this deep link?

hard

A. \n \n \n \n

B. \n \n \n \n \n

C. \n \n \n \n

D. \n \n \n \n \n

Solution

1. Step 1: Check required action and categories for deep links

   Deep links need action VIEW and categories DEFAULT and BROWSABLE to work properly.

2. Step 2: Verify data attributes match the URL pattern

   The URL myapp://user/123 has scheme="myapp", host="user", path="/123". Needs matching scheme, host, and pathPattern="/.*" for variable IDs.

3. Step 3: Compare options

   The filter with scheme="myapp", host="user", pathPattern="/.*", VIEW action, DEFAULT and BROWSABLE matches perfectly. pathPrefix="/user" without host mismatches path="/123". Missing BROWSABLE limits external opening. MAIN/LAUNCHER is incorrect for deep links.

4. Final Answer:

   Intent filter with VIEW action, DEFAULT/BROWSABLE categories, scheme myapp, host user, pathPattern /.* -> Option D

5. Quick Check:

   scheme=myapp host=user pathPattern=/.* VIEW BROWSABLE [OK]

Hint: VIEW action, DEFAULT/BROWSABLE categories, scheme+host+pathPattern [OK]

Common Mistakes:

• Missing BROWSABLE category
• Using MAIN action instead of VIEW
• Confusing pathPrefix with host+pathPattern
• Wrong categories for deep links