This document provides an overview of the Android mobile operating system. It discusses why mobile app development is growing in popularity, including the expanding smartphone market and high demand for developers. It then explains why Android is a good platform, noting its open source nature, wide adoption, and ability to leverage existing Java skills. The document outlines the history and evolution of Android from 2005 to present. It describes the Android architecture, development process, and options for publishing and monetizing apps. Key principles of Android design like performance, responsiveness and security are also summarized.

1. Android Overview
Dr. Josh Dehlinger
Dr. Siddharth Kaza

2. Why Mobile App Development?
 The fact that we can! Only a few years ago you had to
be in the Motorola inner circle to do it!
 Mobile platform is the platform of the future
 Double-digit growth in world-wide smartphone ownership3
 Job market is hot
 Market for mobile software surges from $4.1 billion in 2009 to
$17.5 billion by 20121
 2010 Dice.com survey: 72% of recruiters looking for iPhone app
developers, 60% for Android1
 Dice.com: mobile app developers made $85,000 in 2010 and
salaries expected to rise2
 Students (and faculty!) are naturally interested!
1 http://www.businessweek.com/technology/content/oct2010/tc20101020_639668.htm
2 http://it-jobs.fins.com/Articles/SB129606993144879991/Mobile-App-Developers-Wanted-at-Ad-Agencies
3http://www.gartner.com/it/page.jsp?id=1466313

3. Why Android?
 A lot of students have them
 2010 survey by University of CO1
: 22% of college
students have Android phone (26% Blackberry, 40%
iPhone)
 Gartner survey2
: Android used on 22.7% of
smartphones sold world-wide in 2010 (37.6%
Symbian, 15.7% iOS)
 Students already know Java and Eclipse
 Low learning curve
 CS0 students can use App Inventor for Android
1http://testkitchen.colorado.edu/projects/reports/smartphone/smartphone-appendix1/
2http://www.gartner.com/it/page.jsp?id=1543014

4. Why Android?
 Transferring app to phone is trivial
 Can distribute by putting it on the web
 Android Market for wider distribution
• It’s not 1984

5. Types of
Android
Devices

6. Various Android Phones
http://cloud.addictivetips.com/wp-content/uploads/2010/09/and

7. Galaxy Tablet
http://www.samsung.com/global/microsite/galaxytab/10.1/index.html

8. Android-Powered Microwave
http://www.pocket-lint.com/news/30712/android-powered-microwave-cooking-google
By Touch Revolution – at CES 2010

9. http://www.google.com/nexus/
Google/Samsung Galaxy Nexus

10. Brief History
 1996
 The WWW already had websites with color and
images
 But, the best phones displayed a couple of lines
of monochrome text!
 Enter:
 Wireless Application Protocol (WAP) – stripped down
HTTP for bandwidth reduction
 Wireless Markup Language (WML) – stripped down
HTML for content

11. Brief History
 Many issues (WAP = “Wait And Pay”)
 Few developers to produce content (it wasn’t fun!)
 Really hard to type in URLs using the small
keyboards
 Data fees frightfully expensive
 No billing mechanism – content difficult to
monetize
 Other platforms emerged
 Palm OS, Blackberry OS, J2ME, Symbian
(Nokia), BREW, OS X iPhone, Windows Mobile

12. Brief History - Android
 2005
 Google acquires startup Android Inc. to start Android platform
 Work on Dalvik VM begins
 2007
 Open Handset Alliance announced
 Early look at SDK
 2008
 Google sponsors 1st
Android Developer Challenge
 T-Mobile G1 announced
 SDK 1.0 released
 Android released open source (Apache License)
 Android Dev Phone 1 released

13. Brief History cont.
 2009
 SDK 1.5 (Cupcake)
 New soft keyboard with “autocomplete” feature
 SDK 1.6 (Donut)
 Support Wide VGA
 SDK 2.0/2.0.1/2.1 (Eclair)
 Revamped UI, browser
 2010
 Nexus One released to the public
 SDK 2.2 (Froyo)
 Flash support, tethering
 SDK 2.3 (Gingerbread)
 UI update, system-wide copy-paste

14. Honeycomb
Android3.0-3.
Brief History cont.
 2011
 SDK 3.0/3.1/3.2 (Honeycomb) for tablets only
 New UI for tablets, support multi-core processors
 SDK 4.0/4.0.1/4.0.2/4.0.3 (Ice Cream Sandwich)
 Changes to the UI, Voice input, NFC
Ice cream Sandwic
Android 4.0+

15. The Android Developer
Website
 http://developer.android.com/index.html
 This should be your homepage for the next
semester!

16. Distribution of Devices
Data collected during a 14-day period ending on January 3, 2012
http://developer.android.com/resources/dashboard/platform-versions.html

17. What is Google Android?
 A software stack for mobile devices that includes
 An operating system
 Middleware
 Key Applications
 Uses Linux to provide core system services
 Security
 Memory management
 Process management
 Power management
 Hardware drivers

18. Android Architecture
More details at: http://developer.android.com/guide/basics/what-is-android.html

19. Mobile Devices: Advantages (as
compared to fixed devices)
 Always with the user
 Typically have Internet access
 Typically GPS enabled
 Typically have accelerometer & compass
 Most have cameras & microphones
 Many apps are free or low-cost

20. Mobile Devices: Disadvantages
 Limited screen size
 Limited battery life
 Limited processor speed
 Limited and sometimes slow network access
 Limited or awkward input: soft keyboard, phone
keypad, touch screen, or stylus
 Limited web browser functionality
 Range of platforms & configurations across
devices

21. Mobile Applications
 What are they?
 Any application that runs on a mobile device
 Types
 Web apps: run in a web browser
 HTML, JavaScript, Flash, server-side components,
etc.
 Native: compiled binaries for the device
 Often make use of web services

22.  Development
process for an
Android app
http://developer.android.com/guide/developing/index.html

23. Android Apps
 Built using Java and new SDK libraries
 No support for some Java libraries like Swing &
AWT
 Oracle currently suing Google over use
 Java code compiled into Dalvik byte code
(.dex)
 Optimized for mobile devices (better memory
management, battery utilization, etc.)
 Dalvik VM runs .dex files

24. Building and running
 ADB is a client server program that connects clients on developer
machine to devices/emulators to facilitate development.
 An IDE like Eclipse handles this entire process for you.
http://developer.android.com/guide/developing/building/index.html#detailed-build
Compiled resources
(xml files)
Android Debug Bridge

25. Building and running (more
details)
 Expand
figure
 Android Interface
Definition
Language (AIDL) –
Definitions to
exchange data
between
applications (think
SOAP)
http://developer.android.com/guide/de
veloping/building/index.html#detailed-
build
Android Asset Packing Tool
Allows processes across
apps to communicate.

26. Applications Are Boxed
 By default, each app is run in its own Linux
process
 Process started when app’s code needs to be
executed
 Threads can be started to handle time-consuming
operations
 Each process has its own Dalvik VM
 By default, each app is assigned unique Linux ID
 Permissions are set so app’s files are only visible to
that app

27. Android Architecture

28. Publishing and Monetizing
 Paid apps in Android Market, various other
markets
 Free, ad-supported apps in Android Market
 Ad networks (Google AdMob, Quattro Wireless)
 Sell your own ads
 Services to other developers
 Ex. Skyhook Wireless (
http://www.skyhookwireless.com/)
 Contests (Android Developer Challenge)
 Selling products from within your app

29. Android Market
 http://www.android.com/market/
Has various categories, allows ratings
Have both free/paid apps
Featured apps on web and on phone
The Android Market (and iTunes/App Store) is
great for developers
 Level playing field, allowing third-party apps
 Revenue sharing

30. Publishing to Android Market
 Requires Google Developer Account
 $25 fee
 Link to a Merchant Account
 Google Checkout
 Link to your checking account
 Google takes 30% of app purchase price

32. Android Design Philosophy
 Applications should be:
 Fast
 Resource constraints: <200MB RAM, slow processor
 Responsive
 Apps must respond to user actions within 5 seconds
 Secure
 Apps declare permissions in manifest
 Seamless
 Usability is key, persist data, suspend services
 Android kills processes in background as needed

33. Leveraging the web
 To keep your apps fast and responsive,
consider how you can leverage the web
 What ____________ can be ________ on a
server or in the cloud?
 Tasks/performed
 Data/persisted
 Data/retrieved
 Beware, data transfer is also expensive and can
be slow

34. Other design principles
 http://developer.android.com/design/index.html
 Great reference!

35. Apple vs. Google
 Open Handset Alliance
 30+ technology companies
 Commitment to openness, shared vision, and
concrete plans
 Compare with Mac/PC battles
 Similar (many PC manufacturers, one Apple)
 Different (Microsoft sells Windows, Google gives
away Android)