Android

What is Android? A mobile device operating system. Seen primary in tablets and Cellphones. Based on a Linux kernel. Applications are Java Based Open source and given freely to both developers and cellphone manufactures

How hard is it to make an app? Not difficult at all. If you know Java you practically know Android. Google provides all the tools. Google provides comprehensive tutorials. Many matured book resources available

Main concepts to an Android Application Java Android SDK XML Android VM

Android SDK The Android SDK includes everything to connect an application to the UI and comes with the emulator and a simple GUI creator. Android tools GUI tools Application Emulator

SDK connecting Java to a GUI

XML From Wikipedia Extensible Markup Language (XML) is a set of rules for encoding documents in machine-readable form. It is defined in the XML 1.0 Specification[4] produced by the W3C, and several other related specifications, all gratis open standards.[5] The design goals of XML emphasize simplicity, generality, and usability over the Internet.[6] It is a textual data format with strong support via Unicode for the languages of the world. Although the design of XML focuses on documents, it is widely used for the representation of arbitrary data structures, for example in web services.

Android and XML Android uses XML for anything that isn't the actual program. GUI. Information about the program, i.e. the version Enables future web based extensions (XML is primarily web)

XML Android does it for you GUI to XML

Android Virtual Device A virtual machine used for testing applications Allows Developers to test a wide range of device. These devices could be a tablets, cellphones or low powered computers. It's a VM, thus allows consistent testing to happen on any computer set up with the SDK!

How to make an app. Setting Up. You need Eclipse Plugin Android SKD

Run the SDK Simply hit accept all The update will take a while. Start installing the add on.

To install the plug in Start Eclipse Go to Help, install new software

Getting Started developer.android.com/resources/tutorials/ Android applications launched from eclipse run off a Virtual Machine (Android Virtual Device) To set up the ADV in eclipse window-> Android SDK and AVD Manager. Click New Use next frame as a guide for settings

Create a new Project Application name. This is the human-readable title for your application Package name. This is the package namespace. Think Java Name space Create Activity. Creates a class, and auto creates the “onCreate” method. onCreate, think of it as “main” Min SDK Version. The minimum Android API to run the application.

Programming Main concepts No main, instead an onCreate method. This should be auto defined in new set up or manually added later Listeners and observers. You tell Android what method is connected to what buttons GUI

Launcher Example This should be auto- generated for you assuming a correct project set up.

Listener Example

Listener XML (different applications)

Create GUIs GUIs are rarely manually created. There are generators for Android for GUIs. Droid Draw. A Drag and Drop style application. Not perfect, but great for quickly making a slick interface.

So you think you can develop It's easy, it's simple and you can make a lot of money! What else is there to think about? Fees: cost to actually sell an application. Development hurdles. How does Android stand up to Apple?

Google fees To sell an application, one must have a Google Checkout account. Google charges 20 dollars for the account. Google also charges 3% to withdraw your profits. This is in addition to the 30% cut for selling an app. In the end, Google consumes 33% of your sale price.

Issues with Android Development The strength of Google Android platform is its flexibility. Anyone can put their version of Android on any hardware. This is a pain for developers. Random amount of RAM, different CPUs, screen sized and manufacture changes to the phone make it almost impossible to make completely compatible applications.

Solutions Testing A developer just simply has to test using the AVDs and watch for error reports. The android SDK should stop most compatibility issues. High resource applications should consider putting system requirements.

Conclusion Android is a great platform gaining strength every day. If your main goal is to make as much money as possible creating applications, it is still better to go with Apple. If you want to make apps quickly and with less hassle go with Android. Apple is extremely strict with their sales process and requirements