Introduction to Android Instant Apps

Android Instant Apps are the new kid in the large town of Android-city. The promise behind it is quite simple and groundbreaking at the same time: running native Android apps instantly on your device, without installation.

In this session we will first introduce this evolution in app sharing and discovery mostly from a user perspective. Secondly, we will discover how, as a developer, you can build an Android Instant Apps and deliver this new experience frictionless to all of your users.

Transcript

1. Introduction to Android
   Instant Apps
   by Cyril Mottier
   

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3. >
   

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4. >
   >
   

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5. > > >
   

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6. Find Install Start Setup Use
   Installing & using a mobile app is a
   long and steep path
   

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7. Reduce friction
   as much as possible
   

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8. Instant apps
   Native apps, without installation
   

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10. >
    

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11. >
    >
    

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12. You may only need 10% of an app’s features
    So why download 100%?
    

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13. Application
    

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14. Application
    Feature 1 Feature 2 Feature 3
    Common
    

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15. The build output now depends
    on the targeted run mode
    

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16. installable.apk
    Feature 1
    Feature 2 Feature 3
    Common
    

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17. instant_app.zip
    Feature 1
    APK
    Feature 2
    APK
    Feature 3
    APK
    Base APK
    

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18. What about the
    on-device behaviour?
    

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19. Installable app
    

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20. Feature 1
    Feature 2 Feature 3
    Base
    Installable app
    

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21. Instant app
    

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22. Feature 1
    Base
    Instant app
    Using feature 1
    

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23. Feature 2
    Base
    Instant app
    Using feature 2
    

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24. Feature 1
    Base
    Instant app
    Using feature 1 then 2
    

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25. Feature 1
    Feature 2
    Base
    Instant app
    Using feature 1 then 2
    

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26. Feature 1
    Feature 2 Feature 3
    Base
    Instant app
    Using all features
    

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27. Lollipop+
    

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28. Android Studio 3.0+
    with Instant Apps Development SDK
    

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29. Runtime permissions
    introduced in Android 6.0 (API level 23)
    

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30. App links
    Associate your app with your domain
    

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31. 
    
    
    
    
    
    android:host="${host}"
    android:path="/licenses" />
    
    android:autoVerify="true"
    

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32. 
    
    
    
    
    
    android:host="${host}"
    android:path="/licenses" />
    
    android:autoVerify="true"
    

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33. 
    
    
    
    
    
    android:host="${host}"
    android:path="/licenses" />
    
    android:autoVerify="true"
    

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34. https:///.well-known/assetlinks.json
    

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35. https:///.well-known/assetlinks.json
    [
    {
    "relation": [
    "delegate_permission/common.handle_all_urls"
    ],
    "target": {
    "namespace": "android_app",
    "package_name": "com.gdgnantes.devfest.android",
    "sha256_cert_fingerprints": [
    "1A:24:9C:B5:69:5F:B5:21:CD:80:45:7A:06:20:C5:78:DB:
    07:A8:CA:A0:8F:E9:47:B9:F6:A5:60:6B:78:DB:32"
    ]
    }
    }
    ]
    

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36. https:///.well-known/assetlinks.json
    [
    {
    "relation": [
    "delegate_permission/common.handle_all_urls"
    ],
    "target": {
    "namespace": "android_app",
    "package_name": "com.gdgnantes.devfest.android",
    "sha256_cert_fingerprints": [
    "1A:24:9C:B5:69:5F:B5:21:CD:80:45:7A:06:20:C5:78:DB:
    07:A8:CA:A0:8F:E9:47:B9:F6:A5:60:6B:78:DB:32"
    ]
    }
    }
    ]
    "relation": [
    "delegate_permission/common.handle_all_urls"
    ]
    

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37. https:///.well-known/assetlinks.json
    [
    {
    "relation": [
    "delegate_permission/common.handle_all_urls"
    ],
    "target": {
    "namespace": "android_app",
    "package_name": "com.gdgnantes.devfest.android",
    "sha256_cert_fingerprints": [
    "1A:24:9C:B5:69:5F:B5:21:CD:80:45:7A:06:20:C5:78:DB:
    07:A8:CA:A0:8F:E9:47:B9:F6:A5:60:6B:78:DB:32"
    ]
    }
    }
    ]
    "namespace": "android_app"
    "target": {
    }
    

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38. https:///.well-known/assetlinks.json
    [
    {
    "relation": [
    "delegate_permission/common.handle_all_urls"
    ],
    "target": {
    "namespace": "android_app",
    "package_name": "com.gdgnantes.devfest.android",
    "sha256_cert_fingerprints": [
    "1A:24:9C:B5:69:5F:B5:21:CD:80:45:7A:06:20:C5:78:DB:
    07:A8:CA:A0:8F:E9:47:B9:F6:A5:60:6B:78:DB:32"
    ]
    }
    }
    ]
    "package_name": "com.gdgnantes.devfest.android"
    "target": {
    }
    

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39. https:///.well-known/assetlinks.json
    [
    {
    "relation": [
    "delegate_permission/common.handle_all_urls"
    ],
    "target": {
    "namespace": "android_app",
    "package_name": "com.gdgnantes.devfest.android",
    "sha256_cert_fingerprints": [
    "1A:24:9C:B5:69:5F:B5:21:CD:80:45:7A:06:20:C5:78:DB:
    07:A8:CA:A0:8F:E9:47:B9:F6:A5:60:6B:78:DB:32"
    ]
    }
    }
    ]
    "sha256_cert_fingerprints": [
    "1A:24:9C:B5:69:5F:B5:21:CD:80:45:7A:06:20:C5:78:DB:
    07:A8:CA:A0:8F:E9:47:B9:F6:A5:60:6B:78:DB:32"
    ]
    "target": {
    }
    

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40. https:///.well-known/assetlinks.json
    [
    {
    "relation": [
    "delegate_permission/common.handle_all_urls"
    ],
    "target": {
    "namespace": "android_app",
    "package_name": "com.gdgnantes.devfest.android",
    "sha256_cert_fingerprints": [
    "1A:24:9C:B5:69:5F:B5:21:CD:80:45:7A:06:20:C5:78:DB:
    07:A8:CA:A0:8F:E9:47:B9:F6:A5:60:6B:78:DB:32"
    ]
    }
    }
    ]
    

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41. Modularise your code
    Break the app into features
    

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42. Pointing out
    features
    

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43. Licenses
    :features:licenses module
    Installable app
    :app module
    About
    :features:about module
    

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44. What about the base APK?
    contains code/resources used in all modules
    

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45. Application icon
    Custom font management
    Common styles, dimens, colors, …
    Base Activity/Fragment implementation
    Utilities
    etc.
    What about the base APK?
    contains code/resources used in all modules
    

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46. Modularize
    action in Android Studio
    

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47. ./settings.gradle
    include ':app',
    ':features:about',
    ':features:base',
    ':features:licenses',
    ':instant'
    

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48. include ':app',
    ':features:about',
    ':features:base',
    ':features:licenses',
    ':instant'
    ./settings.gradle
    ':app'
    

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49. include ':app',
    ':features:about',
    ':features:base',
    ':features:licenses',
    ':instant'
    ':features:base'
    ./settings.gradle
    

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50. include ':app',
    ':features:about',
    ':features:base',
    ':features:licenses',
    ':instant'
    ':features:about'
    ./settings.gradle
    

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51. include ':app',
    ':features:about',
    ':features:base',
    ':features:licenses',
    ':instant'
    ':instant'
    ./settings.gradle
    

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52. apply plugin: 'com.android.feature'
    android {
    //...
    baseFeature true
    }
    dependencies {
    application project(':app')
    feature project(':features:about')
    feature project(':features:licenses')
    }
    ./features/base/build.gradle
    

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53. apply plugin: 'com.android.feature'
    android {
    //...
    baseFeature true
    }
    dependencies {
    application project(':app')
    feature project(':features:about')
    feature project(':features:licenses')
    }
    ./features/base/build.gradle
    apply plugin: 'com.android.feature'
    

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54. apply plugin: 'com.android.feature'
    android {
    //...
    baseFeature true
    }
    dependencies {
    application project(':app')
    feature project(':features:about')
    feature project(':features:licenses')
    }
    ./features/base/build.gradle
    baseFeature true
    

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55. apply plugin: 'com.android.feature'
    android {
    //...
    baseFeature true
    }
    dependencies {
    application project(':app')
    feature project(':features:about')
    feature project(':features:licenses')
    }
    ./features/base/build.gradle
    application project(':app')
    feature project(':features:about')
    feature project(':features:licenses')
    

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56. apply plugin: 'com.android.feature'
    android {
    //...
    baseFeature true
    }
    dependencies {
    application project(':app')
    feature project(':features:about')
    feature project(':features:licenses')
    }
    ./features/base/build.gradle
    

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57. apply plugin: 'com.android.feature'
    //...
    dependencies {
    implementation project(':features:base')
    }
    ./features/about/build.gradle
    

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58. apply plugin: 'com.android.application'
    //...
    dependencies {
    implementation project(':features:base')
    implementation project(':features:about')
    implementation project(':features:licenses')
    }
    ./app/build.gradle
    

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59. apply plugin: ‘com.android.instantapp'
    //...
    dependencies {
    implementation project(':features:base')
    implementation project(':features:about')
    implementation project(':features:licenses')
    }
    ./instant/build.gradle
    

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60. apply plugin: ‘com.android.instantapp'
    //...
    dependencies {
    implementation project(':features:base')
    implementation project(':features:about')
    implementation project(':features:licenses')
    }
    ./instant/build.gradle
    apply plugin: ‘com.android.instantapp'
    

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61. apply plugin: ‘com.android.instantapp'
    //...
    dependencies {
    implementation project(':features:base')
    implementation project(':features:about')
    implementation project(':features:licenses')
    }
    ./instant/build.gradle
    

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62. where
    Function returning the binary size of
    Total download bundle binary size
    

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63. where
    Function returning the binary size of
    Maximum download bundle binary size
    

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64. Maximum download bundle size
    (i.e. that weird “ ” constant)
    

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65. During
    development
    ∞
    Maximum download bundle size
    (i.e. that weird “ ” constant)
    

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66. Play Store
    dev tracks
    10MB
    During
    development
    ∞
    Maximum download bundle size
    (i.e. that weird “ ” constant)
    

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67. 4MB
    Play Store
    production
    Play Store
    dev tracks
    10MB
    During
    development
    ∞
    Maximum download bundle size
    (i.e. that weird “ ” constant)
    

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68. The smaller, the better
    (not specific to Android only)
    

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69. Slim down your
    APK size
    

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70. Slim down your
    APK size
    Resource shrinking
    

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71. Slim down your
    APK size Code minification
    Resource shrinking
    

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72. Slim down your
    APK size Code minification
    Vector graphics
    Resource shrinking
    

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73. Slim down your
    APK size Code minification
    Vector graphics
    Resource shrinking
    

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74. Slim down your
    APK size
    Dependencies reduction
    Code minification
    Vector graphics
    Resource shrinking
    Downloadable fonts
    Resources de-duplication
    Remote fetching
    Images optimisation
    WebP format
    Granular dependencies
    Density bucket removal
    Native code architecture removal
    Wear 2.0 APK distribution
    Sparse translation elimination
    Version collapsing
    

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75. APK Analyser
    

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76. APK Analyser
    

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77. Still not enough?
    Configuration split to the rescue
    

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78. android {
    //...
    generatePureSplits true
    splits {
    abi { enable true }
    density { enable true }
    language {
    enable true
    include "en", "fr"
    }
    }
    }
    ./base.build.gradle
    

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79. Installation
    prompts
    

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80. dependencies {
    //...
    implementation 'com.google.android.instantapps:instantapps:1.1.0'
    }
    ./features/base/build.gradle
    

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81. if (InstantApps.isInstantApp(this)) {
    val postInstallIntent = MainActivity.newIntent()
    InstantApps.showInstallPrompt(this, postInstallIntent,
    INSTALL_PROMPT_REQUEST_CODE, "Referrer")
    }
    

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82. Keep user state
    after app installation
    

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83. Cookie API
    // Instant app
    with(packageManager) {
    if (cookie.size <= instantAppCookieMaxBytes) {
    updateInstantAppCookie(cookie)
    }
    }
    

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84. // Installable app
    val cookie = packageManager.instantAppCookie
    // ... (i.e. restore user data)
    packageManager.clearInstantAppCookie()
    Cookie API
    

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85. Instant App Data
    dependencies {
    //...
    implementation 'com.google.android.gms:play-services-instantapps:11.4.2'
    }
    ./features/base/build.gradle
    

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86. Instant App Data
    val client = InstantApps.getInstantAppsClient(this)
    val fileTask = client.instantAppData
    fileTask
    .addOnCompleteListener { readData(it.result) }
    .addOnFailureListener { handleException(it) }
    

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87. Instant App Data
    Shared Preferences
    getFilesDir()
    getDir(String, int)
    Databases
    ParcelFileDescriptor
    to the caller's Instant App's data
    

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88. Instant Apps in the real world
    aka the pros and cons
    

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89. VS
    Instant
    apps
    Progressive
    Web apps
    

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90. Thank you!
    cyrilmottier.com
    @cyrilmottier
    

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