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

Why should we focus more

on next billion ?

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

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

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)

It’s a Different Ballgame

● Slow and Expensive Internet

● Prepaid is used by >95% of users

● Mobile first

In short, we have to rethink

about the parameters we

consider when we are

building mobile apps

Top 11 Best Practices:Building for the next Billion Users*

* Also the last billion, and the billion after the next

#11Responsiveness

Touch Latency

“A time delay between the cause and the effect”

--Wikipedia

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

#10Design

● Material design guidelines an extensive multi-year effort

● Make user intuitively know how to use your app

● Adaptive design methodology

Material Design Spec

google.com/design/spec

#9Anticipate

Prefetch Content

Anticipate what content your users may want

and have it ready

Take advantage of good device state, be

conservative instead

Prefetch Content

Use JobScheduler for Android 5.0+

There are alternatives for Android < 5.0:

● Android Job by Evernote

● GCM Network Manager

Using Job Scheduler

goo.gl/nK8X8g

#8Mobile Data isValuable

Be smart about mobile data usage

Mobile Data mostly hast monthly quota and

cost real money

Smartphones aren’t as smart without

mobile data

Be smart about mobile data usage

Mobile Data mostly hast monthly quota and

cost real money

Smartphones aren’t as smart without

mobile data

Managing Network Usage

goo.gl/AZA23R

#7WebP

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

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

#6Put your APK On a Diet

Put your APK on diet

APK size matters

Google Play smart app updates can help

Avoid users turning off auto-updates

Put your APK on diet

● Choose drawable assets carefully

○ Remember assets scaled down look OK but 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

#5Smooth like Butter

Keep graphics performance smooth

Aim for 60fps, this allows for ~16ms per frame

(1000/60)

Reduce “actual latency” - easier said than done

Keep graphics performance 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

#4Battery

Primary consumer of battery:● Screen

● Mobile Network

● Inability to enter into low power mode

Reduce Battery Usage

● Avoid holdingWakeLocks directly

○ Use FLAG_KEEP_SCREEN_ON and WakefulBroadcastReceiver

● 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

Battery Historian

adb shell dumpsys batterystats

#3Memory

Reduce Memory Usage

Avoid long running services -

be a good citizen

More background memory

usage leads to slower

multitasking and less system

efficiency

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

Memory Monitor

#2Architecture

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

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

#1Good app comes

from good codes

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.

Good code is understandable

codeUnderstandable 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.

Good codes aspects

• Syntax

•Architecture

•Workflow

Learn more

Start to write a

better code to

write a better

future!

Say Good Bye to a Spaghetti Code

#0Summary

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

Thanks