Android Overview

1. Android Overview Shashank Kailash Gajbhiye

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!

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

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

7. Galaxy Tablet

8. Android-Powered Microwave By Touch Revolution – at CES 2010

9. 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. 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 Honeycomb Android 3.0-3.2 Ice cream Sandwich 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

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. Compiled resources (xml files) Android Debug Bridge http://developer.android.com/guide/developing/building/index.html#detailed-build

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

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 • 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)