Droidcon Montreal 2015: Optimizing Your Apps For Emerging Markets

Talk that I gave at Droidcon Montreal 2015 about ways in which you can optimize your apps for markets which are driving the growth of smartphones.

1. Optimizing Your Apps For Emerging Markets #DroidconMtl
3. Emerging Markets Drive Growth
4. Source: Mediacells via The Guardian
5. Source: Mediacells via The Guardian
6. 44 36 21 51 37 11 80 10 9 25 66 9 Smartphone Feature phone Multimedia phone Brazil Russia India China
7. 1. Optimizing App Size
8. The smaller, the better
9. Color Filters
10. Use Color Filter • Faster way to experiment with color schemes. • Reduce the number of assets, which in turn reduc the apk size. • Less memory used as the number of assets are reduced.
11. Code ImageView redCircle = (ImageView) findV iewById(R.id.circle_red_imageview); ImageView greenCircle = (ImageView) findV iewById(R.id.circle_green_imageview); ImageView blueCircle = (ImageView) findV iewById(R.id.circle_blue_imageview); // we can create the color values in different ways: redCircle.getDrawable().setColorFilter(C olor.RED, PorterDuff.M ode.M U LTIPLY ); greenCircle.getDrawable().setColorFilter(0xff00ff00, PorterDuff.M ode.M U LTIPLY ); blueCircle.getDrawable().setColorFilter(getResources().getColor(R.color.blue),PorterDuff.M ode. M U LTIPLY );
12. Image Optimizations Color Filters
13. JPEG WEBP PNG GIF Lossy Lossless Transparenc y Animation WebP
14. No Noticeable Change PNG 24 kb WebP 10 kb
15. Compatibility • You can use the native WebP decoder on 4.2 and later. • For lower versions, use libpng to convert to PNG format and then use it in the app.
16. Other Libraries • Use programs like OptiPNG, TruePNG and PNGC to significantly reduce the size of PNG images. • Use mozjpeg for jpeg images. • 5-10% size reduction • Won’t cause any visible changes to the images.
17. Remove Unused Content Image Optimizations Color Filters
18. Remove Unused Content • Use Resource Shrinking.
19. Code android { ... buildTypes { release { minifyEnabled true shrinkResources true proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro' } } }
20. Remove Unused Content • Use Resource Shrinking. • Use tools like Lint and ProGuard. • Use Android-Unused-Resources jar file if you are still using Eclipse. https://code.google.com/p/android-unused-resources/
21. 2. Optimizing Network Calls
22. Expensive Data Flaky Networks Challenges
23. Build for Failure
24. Most efficient way to transfer is to not transfer
25. Image Scaling
26. Appropriate Image Size • Store multiple image sizes on the server • Low-res devices might never need a full resolutio image • Most times the smallest image size is sufficient.
28. Checksum Image Scaling
29. Client A Client B Server Checksum ID Send File ID Transfer File CS ID
30. Code public static String getM D5EncryptedString(String encTarget){ M essageDigest mdEnc = null; mdEnc = M essageDigest.getInstance("M D5"); // Encryption algorithm mdEnc.update(encTarget.getBytes(), 0, encTarget.length()); String md5 = new BigInteger(1, mdEnc.digest()).toString(16); while ( md5.length() < 32 ) { md5 = "0"+md5; } return md5; }
31. Checksum • Avoid transfers as much as possible. • For file transfers, first compute the md5 checksum and send it to the server to check if it already exis on the server. • The cost to upload the entire file again can be avoided.
32. Image Scaling Checksum Transfer in Blocks
33. Transfer in blocks • Do data transfers in blocks. • Keep track of the blocks that have been transferre and yet to be transferred. • The block size can vary based on the type of connection.
34. Testing for different networks is a pain
35. Testing for different networks • Facebook recently open-sourced Augmented Traf Control (ATC). • It is a tool to simulate network conditions. • It can simulate 2G, Edge, 3G, and LTE networks. • Has multiple profiles for a lot of different countri http://facebook.github.io/augmented-traffic-control/
36. 3. Optimizing for Differen Phones
37. Small Screens Slow Processing Challenges
38. Developing for flagship devices is easy
39. Year Class
41. Code int year = Y earC lass.get(getA pplicationContext()); if (year >= 2013) { // Do advanced animation } else if (year > 2010) { // Do simple animation } else { // Phone too slow, don't do any animations } https://github.com/facebook/device-year-class
42. Redesign Year Class
43. Redesign • Remove features from low-end devices if they wo have the best user experience. • This could be animations, videos or even functionalities. • No feature >>> Bad feature
44. @vinaygaba Questions?