Building for the next billion users

Learn how to write a good android app

Transcript

1. Building for theNext Billion Users Sidiq Permana Google Developer Expert and Intel Android Software Innovator TechMagician at Nusantara Beta Studio ID-Android Developer Tech Talk #4 Malang, April 2 2016
2. Why should we focus more on next billion?
3. 1.4 Bilion+ Active Android Users 400 OEMs and 500 Carriers Able to sell your app in 130 Countries Disribute to 190+ Countries 65 Countries that you can tailor your app pricing
4. Data source: GSMA https://gsmaintelligence.com/metrics/1/0/data/?report=535ac4dab8137 Internet penetration per country: ITU Measuring the Information Society http://www.itu.int/en/ITU-D/Statistics/Pages/publications/anapub.aspx 1 billion new users are expected to come online by 2017, mostly from emerging market
5. D World Bank country GDP classification: http://data.worldbank.org/about/country-and-lending-groups Human development index: http://hdr.undp.org/en/countries Socio-economic statistics: www.gapminder.org OECD countries: www.oecd.org 78% of the world’s population lives in emerging markets (5.7 billion people)
10. It’s a Different Ballgame • Slow and Expensive Internet • Prepaid is used by >95% of users • Mobile first
11. In short, we have to rethink about the parameters we consider when we are building mobile apps
12. Top 11 Best Practices: Building for the next Billion Users* * Also the last billion, and the billion after the next
13. #11 Responsiveness
14. Touch Latency “A time delay between the cause and the effect” --Wikipedia
15. Reducing Perceived Latency • Every UI action should have an immediate visible reaction ◦ Hide/show views, scrolling views, state changes • Every touchable item should have touch feedback ◦ Use touch ripple from android 5.0+ Material: Responsive Design goo.gl/zMDilf
17. #10 Design
18. • Material design guidelines an extensive multi-year effort • Make user intuitively know how to use your app • Adaptive design methodology Material DesignSpec google.com/design/spec
20. #9 Anticipate
21. Prefetch Content Anticipate what content your users may want and have it ready Take advantage of good device state, be conservative instead
22. Prefetch Content Use JobScheduler forAndroid 5.0+ There are alternatives forAndroid < 5.0: • Android Job by Evernote • GCM Network Manager Using Job Scheduler goo.gl/nK8X8g
24. #8 Mobile Data isValuable
25. Be smart about mobile data usage Mobile Data mostly hast monthly quota and cost realmoney Smartphones aren’t as smart without mobile data
26. Be smart about mobile data usage Mobile Data mostly hast monthly quota and cost realmoney Smartphones aren’t as smart without mobile data Managing Network Usage goo.gl/AZA23R
28. #7 WebP
29. What is WebP? • Open Source • Support lossy and lossless format • Supported Natively on Android since 4.0 and with Lossless Format since 4.2; Supported in Chrome and Opera • 24-34% better compression than JPEG; 28% better than PNG with little to no loss in visible quality
30. Why WebP? • Reduce network usage • Reduce bundled image asset sizes in your app/game for faster installs and updates • Downside is encoding and hosting multiple formats WebP for developers goo.gl/laQtI4
31. #6 Put your APK On a Diet
33. Put your APK on diet APK size matters Google Play smart app updates can help Avoid users turning off auto-updates
34. Put your APK on diet • Choose drawable assets carefully ◦ Remember assets scaled down look OKbut not the reverse • Launcher icons include up to xxxhdpi ◦ Store in mipmap- directories (eg. mipmap-hdpi) • Remove unused code and resources ◦ minifyEnabled=true ◦ shrinkResources=true • Multiple APK an option but has tradeoffs
35. #5 Smooth like Butter
36. Keep graphicsperformance smooth Aim for 60fps, this allows for ~16ms per frame (1000/60) Reduce “actual latency” - easier said than done
37. Keep graphicsperformance smooth • Minimize layout overdraw and layout depth • Only run UI updates and logic on the UI thread • Memory allocations can cause GC ◦ Images often to blame - use a library like Glide or Picasso • Use on-device tools: GPU profiling and overdraw Performance patterns video series goo.gl/3dBbse
39. #4 Battery
40. Primary consumer of battery: • Screen • Mobile Network • Inability to enter into low power mode
41. Reduce Battery Usage • Avoid holdingWakeLocks directly ◦ Use FLAG_KEEP_SCREEN_ON andWakefulBroadcastReceiver • Use the new JobScheduler API in Android 5.0+ • Batch network transfers and connections • User facing battery blaming and new developer tooling Keeping the device awake goo.gl/EQVB0i
42. Battery Historian adb shell dumpsys batterystats
43. #3 Memory
44. Reduce Memory Usage Avoid long running services - be a good citizen More background memory usage leads to slower multitasking and less system efficiency
45. Reduce Memory Usage • Subclass IntentService not Service • Let the system wake you ◦ GCM,JobScheduler,AlarmManager or other system events • ActivityManager.isLowRamDevice() ◦ ~512MB with 800x480 or less screen • Process stats and new memory monitor
46. Memory Monitor
47. #2 Architecture
48. App Architecture The right app architecture can dramatically improve the user experience Optimize for fast, responsive UI that is not tied to long running operations like networkrequests Google I/O 2014 App github.com/google/iosched
49. App Architecture • Ensure identical network requests are never duplicated ◦ Use a local database for long lived data ◦ Use a bounded disk cache for transitory data • Screens should still be navigable even if network is down • Never block the UI due to a long running operation ◦ Use inline loading spinners if needed ◦ Use AsyncTask but only for UI related background operations
50. #1 Good app comes from good codes
51. Three common problems • It can be difficult to integrate new features as you are worried about compatibility with the existing system. • Time is spent fixing old code, which have developed mysterious bugs that are hard to reproduce and to fix. • You may have forgotten what a lot of the code does, and so you may be afraid that touching it will break the system.
52. Good code is understandable code Understandable code is easier to maintain, easier for new developers to learn, easier to debug, faster to find what you're looking for, and most importantly: helps that the programmers writing the code actually understand business objectives.
53. Good codes aspects • Syntax • Architecture • Workflow
54. Learn more Start to write a better code to write a better future!
55. Say Good Bye to a Spaghetti Code
56. #0 Summary
57. Summary 11. Responsiveness 10. Material Design 9.Anticipate 8. Smart Datausage 7. WebP 6. Put your APK ondiet 5. Smooth likebutter 4. Battery 3. Memory 2. AppArchitecture 1. Good Codes
58. Thanks