Reducing Mobile Data Usage in your Android Apps

In this presentation, we take a look at the different areas in your app that you can improve mobile data usage in. Specifically Server Interactions, Images and APK Package Size.

Transcript

1. @riggaroo
   Reducing Mobile Data
   Usage in your Apps
   Rebecca Franks
   @riggaroo
   

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2. @riggaroo
   Rebecca Franks
   Senior Android Developer & Google Developer
   Expert
   DVT / DStv
   www.riggaroo.co.za
   @riggaroo
   

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3. @riggaroo
   Why should we reduce data usage?
   
   Expensive Mobile Data
   

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4. @riggaroo
   
   Why should we reduce data usage?
   

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5. @riggaroo
   3 Areas to improve
   Images
   
   Bundled App
   
   Server Interactions
   ☁
   

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6. @riggaroo
   Server Interactions
   

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7. @riggaroo
   Features of your API have a
   huge impact on
   performance of your app
   

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8. @riggaroo
   Offline First Design
   

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9. @riggaroo
   Every Request Counts.
   

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10. @riggaroo
    Aggregate on the Backend
    

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11. @riggaroo
    Design your API
    based on the usage
    of your app
    {
    "name": "Rebecca Franks”,
    "profileUrl": "http://riggaroo.co.za/image.jpg",
    "followers": 50,
    "repositories": [
    {
    "name": "Book Dash Android App",
    "id": "bookdash-android-app"
    },
    {
    "name": "MVP Example",
    "id": "mvp-example"
    }
    ]
    }
    

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12. @riggaroo
    Strip unused information
    {
    login: "riggaroo",
    id: 9973046,
    avatar_url: "https://avatars.githubusercontent.com/u/9973046?v=3",
    gravatar_id: "",
    url: "https://api.github.com/users/riggaroo",
    html_url: "https://github.com/riggaroo",
    followers_url: "https://api.github.com/users/riggaroo/followers",
    following_url: "https://api.github.com/users/riggaroo/following{/other_user}",
    gists_url: "https://api.github.com/users/riggaroo/gists{/gist_id}",
    starred_url: "https://api.github.com/users/riggaroo/starred{/owner}{/repo}",
    subscriptions_url: "https://api.github.com/users/riggaroo/subscriptions",
    organizations_url: "https://api.github.com/users/riggaroo/orgs",
    repos_url: "https://api.github.com/users/riggaroo/repos",
    events_url: "https://api.github.com/users/riggaroo/events{/privacy}",
    received_events_url: "https://api.github.com/users/riggaroo/received_events",
    type: "User",
    site_admin: false,
    name: "Rebecca Franks",
    company: null,
    blog: "http://riggaroo.co.za",
    location: "Johannesburg, South Africa",
    email: null,
    hireable: null,
    bio: "Google Developer Expert for Android. Senior Android Developer based in South Africa. ",
    public_repos: 14,
    public_gists: 5,
    followers: 128,
    following: 13,
    created_at: "2014-11-27T06:32:40Z",
    updated_at: "2016-06-03T15:23:57Z"
    }
    {
    login: "riggaroo",
    id: 9973046,
    avatar_url: "https://avatars.githubusercontent.com/u/9973046?v=3",
    url: "https://api.github.com/users/riggaroo",
    html_url: "https://github.com/riggaroo",
    followers_url: "https://api.github.com/users/riggaroo/followers",
    following_url: "https://api.github.com/users/riggaroo/following{/other_user}",
    gists_url: "https://api.github.com/users/riggaroo/gists{/gist_id}",
    starred_url: "https://api.github.com/users/riggaroo/starred{/owner}{/repo}",
    repos_url: "https://api.github.com/users/riggaroo/repos",
    type: "User",
    site_admin: false,
    name: "Rebecca Franks",
    blog: "http://riggaroo.co.za",
    location: "Johannesburg, South Africa",
    bio: "Google Developer Expert for Android. Senior Android Developer based in South Africa. ",
    public_repos: 14,
    followers: 128,
    following: 13,
    }
    

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13. @riggaroo
    GZIP your Data
    Ensure app is requesting GZIP
    

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14. @riggaroo
    Enable HTTP Cache
    Cache-Control: max-stale=3600
    private final OkHttpClient client;
    public CacheResponse(File cacheDirectory) throws Exception {
    int cacheSize = 10 * 1024 * 1024; // 10 MiB
    Cache cache = new Cache(cacheDirectory, cacheSize);
    client = new OkHttpClient.Builder()
    .cache(cache)
    .build();
    }
    

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15. @riggaroo
    Keeping user’s data fresh
    Any new data now?
    And now?
    What about now?
    Have some data
    Have the same data
    Have the same data
    ☁
    

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16. @riggaroo
    Keeping user’s data fresh
    Give me the data
    Have some data
    Have the changed data
    ☁
    Firebase
    Cloud Messaging
    Have the changed data
    

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17. @riggaroo
    Be courteous
    Wait for ideal conditions
    - WiFi + Battery
    Defer unimportant operations
    

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18. @riggaroo
    GcmNetworkManager
    •Schedule one-off vs. periodic tasks.
    •Automatic back-off and failure retry.
    •Awareness of network activity.
    •Awareness of device charging state.
    •Persistence of tasks across boot.
    

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19. @riggaroo
    Give your user options…
    Sync Frequency Image Quality
    

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20. @riggaroo
    Try new things
    Push Messaging
    

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21. @riggaroo
    Tools to monitor
    Data Usage
    

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22. @riggaroo
    Stetho by Facebook (Android)
    Allows you to use Chrome Developer Tools with Android Apps
    - Monitor requests
    - Edit Preferences & Databases
    

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23. @riggaroo
    Charles Proxy
    •HTTP Request Proxying
    •View Web Traffic
    •Throttle connections
    •Intercept Traffic
    •https://www.charlesproxy.com/
    

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24. @riggaroo
    

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25. @riggaroo
    Android Network Monitor
    How and when your app transfers data
    

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26. @riggaroo
    Emulator
    

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27. @riggaroo
    Images
    

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28. @riggaroo
    Don’t download what your
    users wont see.
    

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29. @riggaroo
    Don’t download large images
    for small areas
    fb.com/image1.jpg?w=150 fb.com/image1.jpg?w=400
    

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30. @riggaroo
    Look at Device Pixel Ratio
    fb.com/image.jpg?dpi=0.75 fb.com/image.jpg?dpi=2.0
    Android Low DPI Retina Display
    

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31. @riggaroo
    Don’t download images twice.
    Cache them.
    

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32. @riggaroo
    Download lower quality on slower
    networks.
    

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33. @riggaroo
    Image Compression
    Always use *SAVE FOR WEB*
    

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34. @riggaroo
    zopfliPNG
    ImageMagick
    PNGQuant
    PNGWolf
    PunyPNG Defluff
    TinyPNG
    PNGGauntlet TruePNG
    

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35. @riggaroo
    1.2MB 183KB 201KB
    aaptOptions {
    cruncherEnabled = false
    }
    Custom
    Compression
    AAPT
    

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36. @riggaroo
    • VectorDrawable / ShapeDrawable
    • WebP (4.1 above)
    • Transparent WebP - (4.4 above)
    • JPEG
    • PNG
    Image Types Supported in Android
    

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37. @riggaroo
    VectorDrawable
    WebP
    JPG
    PNG
    Can the image be a VD?
    Do you support WebP?
    Does it need transparency?
    Is it simple or complex?
    Yes
    Yes
    Yes
    Simple
    Complex
    No
    No
    No
    How to decide what type of image to use:
    

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38. @riggaroo
    Bundled Package Size
    Size of your APK
    

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39. @riggaroo
    What is packaged in our APK?
    • App Code
    • classes.dex
    • Native Code (libs/
    /*.so)
    • Resources
    • res/
    • resources.arsc
    (uncompressed!)
    • Misc
    • assets/
    • META-INF/
    • AndroidManifest
    .xml
    .apk
    

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40. @riggaroo
    APK Analyser
    • Demo
    

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41. @riggaroo
    Removing Unused Code
    buildTypes {
    release {
    minifyEnabled true
    shrinkResources true
    proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-project.txt'
    }
    Enable ProGuard + Test
    

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42. @riggaroo
    Removing Unused Code
    android {
    defaultConfig {
    ...
    resConfigs "en", "zu"
    }
    }
    Remove unused configurations
    0.35MB
    SAVED
    4MB -> 3.65MB =
    

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43. @riggaroo
    Build Variants
    • Split APK up
    • Architecture
    • Screen Size
    • Downside - many APKs to test
    android {
    ...
    splits {
    abi {
    enable true
    reset()
    include 'x86', 'armeabi-v7a', 'mips'
    universalApk true
    }
    }
    }
    

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44. @riggaroo
    ArscBlamer
    • resources.arsc file gets big
    • ArscBlamer is a command-line tool that can parse an Android
    app's resources.arsc file and extract useful, actionable
    information about its contents.
    • https://github.com/google/android-arscblamer
    

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45. @riggaroo
    REMEMBER
    Every Request Counts
    Reduce your size of your app
    Optimise your image usage
    

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46. @riggaroo
    Thank you.
    www.riggaroo.co.za
    

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47. @riggaroo
    Links
    • Image Compression for Android Developers- https://www.youtube.com/
    watch?v=r_LpCi6DQME
    • APK Analyser - http://android-developers.blogspot.co.za/2016/05/
    android-studio-22-preview-new-ui.html
    • Network Monitor - https://developer.android.com/studio/profile/am-
    network.html
    • Put your APK on a diet - https://www.youtube.com/watch?v=xctGIB81D2w
    • http://www.slideshare.net/fbrunel/mobile-api-design-techniques-26952520
    • https://code.facebook.com/posts/872547912839369/improving-facebook-s-
    performance-on-android-with-flatbuffers/
    • https://medium.com/@duhroach/smaller-pngs-and-android-s-aapt-
    tool-4ce38a24019d#.vi5zl3tjr
    

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