Best practises how to reduce Android application install size & improve your app install conversation rate. Video can be found here youtu.be/ksgW-VHH-Qo

1. Kirill Rozov
Android Developer
Optimize APK size
GDG Minsk

2. medium.com/googleplaydev/shrinking-apks-growing-installs-5d3fcba23ce2
Average downloaded APK size

3. 64 MB

4. What for?
DownloadAPKsize
0
5
10
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25
Size from Google Play for Xiaomi Mi A1 Android 8.0

5. Why it’s problem?
• Support low-end devices
• Low space on device memory
• How long time it will take to download app
I need it right now!!!
• No Wi-Fi
• Cellular data costs

6. Effect
• Lower install conversion rate
• Google Play Featuring problems
• Google Play Security Checks problems
• Problems with Instant App (4Mb limits)

8. APK Structure

9. APK Structure

10. Size related to app
• APK size
• Initial download size
• On-device install size
• Update download size

11. Size related to app
• APK size
• Initial download size
• On-device install size
• Update download size

12. Graphic Optimizations

13. Image Optimizers

14. PNGQuant ImageMagick PNGGauntlet PNGOut
PNGCrush OptiPNG CryoPNG PNG Compressor
Yahoo Smush.it PNGOptimizer PunyPNG TinyPNG
PNGWolf Advpng DeflOpt Defluff
Huffmix TruePNG PNGng-s9 zopfliPNG

15. ImageOptim

16. Optimization results
9.0 MB

17. Optimization results
6.5 MB

18. Optimization results
228 Images
Save: 28%
Average: 36%
Max saving: 98.6%
6.5 MB

19. Android PNG Cruncher
android {
buildTypes {
release {
// Disable PNG optimisation
crunchPngs false
}
}
}

20. SVGO
github.com/svg/svgo

21. Use WebP

22. PNG vs WebP
PNG, 958 KB WebP 100%, 286 KB-70%

23. PNG vs WebP
PNG, 958 KB WebP 75%, 29 KB-97%

24. Vector graphics

25. Vector graphics
xxxhdpi
3.6 KB
xxhdpi
xhdpi
hdpi
mdpi
2.5 KB 1.6 KB 1.1 KB 0.7 KB
PNG, 100x100dp, 8 bit

26. Vector graphics
Size, bytes
Optimized PNG,
5 files
SVG VectorDrawable Android Shape
RAW 10,023 359 416 232
In APK 10,023 - 371 241

27. Glide + SVG
github.com/kirich1409/SvgGlidePlugins

28. POTrace
PNG SVG
potrace.sourceforge.net

29. Multiple APKs

30. Multiple APKs
android {
splits {
// Configures multiple APKs based on screen density
density {
enable true
// Specifies a list of screen densities Gradle
// should not create multiple APKs for
exclude "ldpi", "xxhdpi", "xxxhdpi"
// Specifies a list of compatible screen size
// settings for the manifest
compatibleScreens 'small', 'normal', 'large', 'xlarge'
}
}
}

31. Reuse graphics

34. Image tint
<ImageView
android:src="@drawable/ic_favorite_black_48dp"
android:tint=“@color/blue"
/>
Drawable.setTint(int)
Drawable.setTint(ColorStateList)

35. Optimize images
• Use image optimizer
• Use WebP
• Use vector graphics
• Use multiple APKs for different screen
• Reuse similar images
• Skip images for low densities

36. Resources
Optimizations

37. Fonts

39. Downloadable fonts

40. Unnecessary
resources

41. Resource shrinker
android {
buildTypes {
release {
minifyEnabled true
shrinkResources true
}
}
}

42. Resource configurations
android {
defaultConfig {
resConfigs ’ru’, ‘en’, ‘es’, ‘fr’, ‘ge’
}
}

43. Resource configurations
android {
defaultConfig {
resConfig ’auto’// Only for localization languages
}
}

44. Resource configurations
android {
defaultConfig {
resConfigs ’ru’, ‘en’, ‘es’, ‘fr’, ‘ge’
resConfigs ’mdpi’, ‘hdpi’, ‘xhdpi’, ‘xxhdpi’
resConfigs ’normal’, ‘large’, ‘xlarge’
}
}

45. Resource Optimizations
• Downloadable fonts
• Remove unused resources
• Reuse resources
• Use recommended media formats
AAC for audio, H264 AVC for Video and etc.
• Update strings over-the-air

46. localise.so

47. Code Optimizations

48. D8 dex compiler

49. DX compilation timeTime(s)
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DX D8
* Tested with benchmark project here

50. .dex file sizeFilesize,MB
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DX D8
* Tested with benchmark project here

51. Code optimizations tools

52. Code optimizations tools
• Java bytecode
• ProGuard
• DexGuard
• R8
• dex
• Facebook ReDex

53. Input JARs
Optimised code
Optimize
Shrunk code
Shrink
Obfuscated code
Obfuscate
Output JARs
Preverify

54. ProGuard Result
Plaid App Results
No optimization Optimization
Optimization
+
obfuscation
.dex size 2.6 Mb 1.2 Mb 0.9 Mb
Classes number 4827 2747 2715
Method references 42664 22319 18922
medium.com/google-developers/practical-proguard-rules-examples-5640a3907dc9

55. External libraries usage

56. External libraries usage
• Remove unused Android Support Library parts
• Try to don’t add libraries for 1 class/method usage
• Reflection based libraries can’t be properly optimised and
shrinked
• Don’t add debug libraries to a release builds
• Facebook Stetho
• LeakCanary
• etc.

57. Native libraries

58. Remove unused ABIs
android {
defaultConfig {
ndk {
abiFilters ‘armeabi-v7a’, ‘arm64-v8a’, ‘x86’
}
}
}

59. Multiple APKs for ABIs
android {
splits {
// Configures multiple APKs based on ABI
abi {
enable true
// Resets the list of ABIs
// that Gradle should create APKs for to none
reset()
// Specifies a list of ABIs
// that Gradle should create APKs for
include ‘armeabi’, ‘armeabi-v7a’, ‘arm64-v8a’
}
}
}

60. Code Optimisations
• Use D8 compiler instead of DX
• Code optimizations & shrinker tools
• Be careful about using external libraries
• Remove support of unused ABIs
• Use multiple APKs for ABIs

61. Other Optimizations

62. APK Structure

63. Packaging options
android {
packagingOptions {
exclude "/okhttp3/**"
exclude "/com/google/api/**"
exclude "/kotlin/**"
exclude "/com/applovin/**.java"
exclude "/META-INF/*.version"
exclude "/META-INF/**.pro"
exclude "/META-INF/services/**"
exclude "**/*.kotlin_module"
exclude "**/*.properties"
exclude "**/*.xml"
}
}

64. Google Play

65. Features
• Special compression format
• File-by-File updates
• Multiple APKs

66. Google Play Multiple APKs
• OpenGL texture compression formats
• Screen sizes and densities
• Device feature sets
• Platform versions
• CPU architectures
• Special APK for Android Go Edition

67. Google Play App Signing
More about App Signing youtu.be/5tdGAP927dk

69. github.com/kirich1409/apk-size-optimization
APK size optimization guide

71. Thanks
kiryl.rozau@apalon.com
krlrozov
Kirill Rozov
Android Developer