Android overview part2

1. 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

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

3. Mobile Devices: Advantages
 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

4. 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 link

5. 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

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

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

8. 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

9. Building and Running

10. 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

11. Android Architecture

12. 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

13. Android Market (Google Play)
 https://play.google.com/store
 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

14. Publishing to Google Play
 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

17. 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