Deep links do not work in Samsung native apps

Question

Samsung Galaxy S6, Android Marshmallow 6.0. Developing with Unity.

Samsung's apps

Deep links https:// do not work, but intent:// do work in:

• Internet app
• Memo app

Google's apps

Both https:// and intent:// do work in:

• Google Chrome app
• Gmail app

Is there something about Samsung custom apps?

Code

assetlinks.json

[{
  "relation": ["delegate_permission/common.handle_all_urls"],
  "target": {
    "namespace": "android_app",
    "package_name": "com.xxx.app",
    "sha256_cert_fingerprints":
    ["4E:CC:14:62:B3:1D:13..."]
  }
}]

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<!-- REPLACE  com.companyname.projectname to your app bundle ID-->
<manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.xxx.app" android:installLocation="preferExternal" android:versionCode="1" android:versionName="1.0">
  <uses-sdk android:minSdkVersion="21" android:targetSdkVersion="23"/>
  <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" android:maxSdkVersion="1" />
  <supports-screens android:smallScreens="true" android:normalScreens="true" android:largeScreens="true" android:xlargeScreens="true" android:anyDensity="true" />
  <application android:icon="@drawable/app_icon" android:label="@string/app_name" android:debuggable="false">
    <activity android:name="causallink.assets.DeepLinkBridge" android:label="@string/app_name">
      <intent-filter>
        <action android:name="android.intent.action.MAIN" />
        <category android:name="android.intent.category.LAUNCHER" />
        <category android:name="android.intent.category.LEANBACK_LAUNCHER" />
      </intent-filter>
      <meta-data android:name="unityplayer.UnityActivity" android:value="true" />
      <meta-data android:name="unityplayer.ForwardNativeEventsToDalvik" android:value="false" />
      <intent-filter android:autoVerify="true">
        <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="v.xxx.com" />
      </intent-filter>
    </activity>
  </application>
</manifest>

😕 P.S. I have googled and found a lot of SO posts, but none of them I found actually helpful.

Answer 1

The "https://" deep links you refer to are using Android's App Links mechanism for opening apps (check this link for a good overview: https://blog.branch.io/technical-guide-to-deep-linking-android-app-links/).

The "intent://" deep links are using Chrome Intents (check: https://blog.branch.io/technical-guide-to-deep-linking-on-android-chrome-intents/).

The Samsung apps you mention simply don't support App Links - support is spotty for App Links generally. The safest path is to support both URI Scheme linking/Chrome intents and App Links, as you will find different apps that support one but not the other - and vice-versa.