The challenge for Android developers when it comes to smart phone app development is how to test their mobile apps. Obviously, testing your app on just one Android mobile would probably be not the smart thing to do. Because there are many brands and models of Android mobile phone out there, sometimes this becomes really daunting for the developer.

(Source: Techcrunch.com)

The best way to approach testing your apps is to do your market research. This means that you have to define your demogrpahics up to the most detailed level like what brand and model of Android phone they are using. If you are developing a weather app for North America for example, then chances are most of Android users have the potential to take interest in your app especially if it it free. Give the above chart of Android devices, you do not need to test your app on all of them.

In such cases, it is good to employ Pareto’s law – or the 80 / 20 rule. Pareto’s law states that “for many events, roughly 80% of the effects come from 20% of the causes”. This is widely known by Sales manager wherein they realize that 20% of their sales force brings in 80% of the revenue. And because this law’s application is quite ubiquitous is other areas, you can apply Pareto’s law in your mobile app testing strategy.

Opensignals have done their research regarding Android devices and displayed their data in graphical form like the one above. By taking 20% of the most widely used Android devices that access Opendata, you should be able to reach more of your target audience with the least amount of effort when it comes to testing. These device are:

• Samsung GT-I9100
• Samsung GT-I9000
• HTC Desire HD
• Samsung GT-S5830
• HTC Desire
• Samsung GT-N700

Market changes from time to time as mobile manufacturers create new models every year. And this is why it is important to do your market research first and not waste time on testing your app on a device that just makes a little impact on the overall marketing strategy of your mobile app.

This is a detailed explanation of the last article regarding android app creation. You can find that article here.

In this Android tutorial you will learn:

- where the project files are located
- define the roles of the project files
- what files create the application’s user interface (UI)
- what files are used for programming the app’s functionality
- understand the programming concepts of this app

Project Files

Since this is a beginners tutorial, it’s good to know what and where the various files were produced to create this simple Hello World app. To find out where the files are produced from your Eclipse editor, just go to Project | Properties and a similar screen found below should appear.

From this screen, look at the location field and there you should find the location of your Hello World android app. In this example, it is /home/htmlpress/workspace-android/Hello World. There are five folders and three files on the main project folder.

Folders:

• assets – does not contain anything for this project.
• bin – contains the binary files i.e. the .apk file. APK files are what you submit to the Google Play website so that others can download your app.
• gen – folders and the file generated here are not to be modified by hand so we shall leave this alone. Contains the R.java file which is an index to all the resources used by your app to which you can refer in your source code.
• res – contains folders and files that renders the look and feel of your app.
• src – contains the java source code of the Hello World app

Files:

• AndroidManifest.xml
• proguard.cfg
• project.properties

These three files are text files.

You should be able to see most, if not all, of these folders and files from your Eclipse editor.

User Interface

The files that construct the user interface for this Hello World android app are found in the res > layout > main.xml in the Package Explorer frame of Eclipse.

The screen above shows the graphical layout of the Hello World app. To look at the code just click on the tab on the lower left hand side called main.xml. You should see the following code:


<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >

</LinearLayout>


So from this code, we can find out that the Linear Layout is used and that a TextView object called hello is used to display a string. This is defined in the TextView tag and the android:text attribute of the mentioned tag. With Android, there are different types of layout you can use which will be the topic of future posts. For now we just want to understand the Hello World app.

To find out the value for the TextView tag, open the file res > values > strings.xml in the Project Explorer frame of Eclipse. You should see the following code:


<?xml version="1.0" encoding="utf-8"?>
<resources>

</resources>


You can then compare the string values here from the AVD screen shot above. From here you can make out where the text comes from. If you plan to do some layout changes, then Google strongly encourages developers to make changes from the two xml layout files mentioned above. This makes your code more readable and lessens the complexity of a mobile app.

Programmatic Source Code

The programmatic code for this Hello World mobile app is found in src > net.htmlpress.helloworld > HelloWorldActivity.java of your Eclipse’s Package Explorer frame. The code should look like the following:


package net.htmlpress.helloworld;

public class HelloWorldActivity extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
}
}


In this code, there is one class – HelloWorldActivity – which is based on the Activity class. In an Android, an Activity is a single application entity that have functions being performed. An application can have more than one Activity where the user can use each one at a time. In this app it only has one. It’s only function is to display a message. An activity can have a user interface or can just run in the background without a UI.

The onCreate method is an event that gets triggered when your application starts. Thus, any code defined in this method get executed when your application starts. Below is a diagram illustrating the various events in an Android application.

The code super.onCreate(savedInstanceState) ensures that the Android state prior to executing your app is saved. Without this, you’ll be getting an unexpected error while starting your application (applies to the version of Android used in this tutorial).

The code setContentView(R.layout.main) sets the Activity’s user interface. Omitting this line of code will give you a blank screen. you would still get the title bar through with the text Hello World. But the layout that includes the Text View object are not included. The setContentView received a view object as a parameter. And the view passed is the desired content to display.

The interesting infographic below shows that 59% of mobile apps do not generate revenue to break even and that there is a correlation between the big spenders and having a successful mobile app. This statistics applies to mobile apps in general.

But what if you develop mobile apps for your website and use it differently?

An example of mobile apps that are developed for websites are the facebook app and twitter app. The twitter app and Twitter as a company haven’t broke even yet when it comes to revenue and expenditures. But its app has a purpose – to get people to use its services and get the traffic for its website. This means that you can think of developing mobile apps for the purpose of generating traffic to your website. And the more traffic you have, the more chances you will have in increasing your conversion rates whether that would be in terms of sales, opt-ins, etc.

There are now 70 million sites that use WordPress as reported by a couple of websites. That’s up 50% from last year’s figure of 35 million! And if you missed this report, 48% of the top 100 blogs are actually developed in WordPress But this should come as no surprise at all. Here are the reasons why WordPress is the most popular tool for developing websites in this day and age.

1 – Easy to install. WordPress has been famous for its 5 minute install. And in most cases they have over delivered. A WordPress install can actually take less than 2 minutes!

2 – Easy to use. Once you have install WordPress, all you have to do is to start posting. And if you can use a popular word editor like MS Word, then you can use the WordPress editor.

3 – Easy to customize. AS long as you know HTML and CSS, you can do your own User Interface customization. And we have that type of tutorial here. Or, if you do not have these skills, then the most easiest way would be select another theme. This makes it appear that you have “customized” your website.

4 – Features can be added easily. You can add features just by installing and activating plug-ins. There’s no programming knowledge needed.

5 – Mobile web app ready. You can install plugins so that your WordPress website can be viewed well with mobile devices.

So, if your website is not developed in WordPress, now is the time to jump on the band wagon.

If you are developing your WordPress website or Android application and are targeting tablet users, it’s good to do some basic research first before doing the development itself. An android web application would mean that the bulk of the work would be in WordPress and HTML 5. A native Android application would mean that the bulk of the work will be in your Android source codes. Since Android tablet devices comes in many flavour, it’s good to know which brand leads the pack. In the US, it is surprising to note that Amazon Kindle is in the lead as reported by TechCrunch.

54.4% Amazon Kindle Fire
15.4% Samsung Galaxy Tab Family
7.0% Motorola Zoom
6.3% Asus Transformer
5.7% Toshiba AT 100
4.3% Acer Picasso
2.1% Acer Iconia
1.3% Dell Streak
1.2% Lenovo Idea Pad
0.7% Sony Tablet S
1.6% Other

The report also found out that the more bigger the screen size is on the tablet, the more page views it generates from the user. The statistics above apply to the US and the rankings would probably be different is you are targeting Android tablet users in an international scale.

Whether you have a WordPress website, a web application or a native mobile application, it’s always good to test these on the devices that your target audience is using. It’s a good thing for Android, you can always create an Android Virtual Device – or AVD – from you PC and see how they render.

If you are creating your own website with WordPress, it’s good to put some fun into it – especially when a visitor visits a page or a post that does not exist. This can happen quite easily as your website grows. Once you posted an article, this gets indexed by the search engines. A number of reasons can occur as to why you may want to delete an indexed post or page. One of the popular reasons is the duration a user stays on that page. If they just stay on the page for 2 seconds, then SEO-conscious website owners would have it deleted or modified. The former is the easier way out. You don’t want your website to be categorized by search engines as that of having low quality post.

When a user visits a link that has been deleted, they usually get an error. So why not put some fun into it? Here’s some websites (not necessarily in WordPress) that have done so.

Domaining.com has a funny picture of a man who seemed to get the electrical wirings wrong when their website went down.

and what about this – a gaming website where you can play games, even if the page you are looking for does not exist.

And some of them are just out of this world!

It’s easy to create your first application in Android once you have a development environment. Thus, the pre-requisites fro this Android tutorial are:

* Create an Android development environment
* Research the audience / device you are targeting and create the AVD

Once you are able to do the above, you are now ready to create your first Android application.

Create An Android App

1 – Start Eclipse
2 – Click File | New | Project…

3 – On the New Project window, select Android | Android Project then click the Next button. The New Android Project window will appear.

4 – On the New Android Project window, enter Hello World in the Project Name text box; click the Next button. The following screen will appear.

5 – On the next New Android Project window, select the SDK to target. In this case Google API 2.2 is selected so that we can use the Huawei Ideos AVD created in the previous post. Click the Next button. The following screen will appear.

6 – On the next New Android Project window, enter net.htmlpress.helloworld in the Package Name text box, then click the Finish button

7 – To run the project, double click on the HelloWorld project in Eclipse’s Package Explorer panel then click on the Run button found at the top of the Eclipse editor. This will launch the default AVD. This is not a problem if you created a single AVD.

If you have multiple AVDs and would like to select a particular one for this project just set your Target configuration to manual in Eclipse. You can do this by clicking the menu Run | Run Configurations… The following screen should appear.

In the Run Configuration screen, select the Target tab and click on the Manual option. Once you run your Android project in Eclipse, the Android Device Choose window will appear and from here you can select what AVD to use.

Once Android is running in your AVD, unlock it by dragging the Arrow to the right. This will take you to the main Android screen. And from here the HelloWorld app will run automatically.

Huawei Ideos is an Android smart phone that is marketed to the masses worldwide. For less than $90 you can purchase this smartphone outright. So if you are planning to target users of this demographics then it’s essential to create and test your Android app on a Huawei Ideos AVD. In order to create one, we first did our research on its technical specifications:

OS – Android 2.2
Display Resolution – 240×320 pixels
Pixel density – 143 ppi

Based on this information, the following AVD is created. The Skin is QVGA which was not mentioned in the first reference but mentioned here.

The AVD specifications are as follows:

Target – Android 2.2; API Level 8
Skin: Built-in – QVGA
Hardware Property:
Abstracted LCD Density = 120
LCD pixel height = 320
LCD pixel width = 240
Max Application VM Heap = 24

When this AVD was started, it didn’t quite match up to the smartphone’s actual size. In order to correct this, play around with its Launch Options settings. These settings appear after you press the Start… button in the AVD Manager.

After coming up with the Launch Options settings above, this AVD appeared which is close enough to the real thing:

Ideos does not come with a physical keyboard because its keyboard is on the screen. Luckily with AVDs you can specify a keyboard outside of the screen to make your testing much easier.

Even before you start developing, it is essential to know who you are developing for. And by this, we mean, defining the Android device where the majority of your audience are. Unlike the iPhone, Android mobile phones are fragmented in the sense that there could be different types of display configuration. This means that if you develop for a Huawei Ideos Android phone, the screen rendition may be different in a Samsung Galaxy mobile phone because the latter has a bigger screen display compared to a Huawei. And the more objects (i.e. buttons, text boxes, etc.) you have on your mobile app, the more testing you will need to do on the different devices.

Realistically you cannot test on all android devices unless you are a big company. But there is a smart work around to do this and it is in the form of AVDs – or Android Virtual Devices. Once you have installed your android development environment decide on what version of Android and the Android device(s) you are targeting for. Listed below are the different versions of Android and their commercial names:

• Eclair – version 2.0 / 2.1
• Froyo – version 2.2 / 2.2x
• Gingerbread – version 2.3 / 2.3x
• Honeycomb – version 3.0 / 3.x
• Ice Cream Sandwhich – version 4.0 / 4.x

Once you have decided this, find out what Android devices came pre-installed with the Android version that you are targeting for. Then research for its technical specifications and then create the AVD.

Create an Android Virtual Device (AVD)

1 – Just start your Android SDK Manager. If you are using Ubuntu, go to Terminal and type Android. You should see the following screen below:

2 – Click on the Tools | Manager AVD

3 – The Android Virtual Device Manager will appear

6 – Fill out the fields based on the technical specifications of a particular smartphone you have researched

7 – Click on the Create AVD button. This should take you back to the Android Virtual Device Manager. To start the AVD you have created, select its AVD Name and click on the Start… button. In this case, Nexus One was selected and after clicking the Start button the following Launch Options screen appeared.

Just press the Launch button to continue in order to load the AVD.

Once you get your AVD running, your ready to develop some web apps!

If you haven’t started your android environment yet, or if you find that there’s too much work setting up an android environment in Ubuntu or Windows, then fret not. There’s an online service where you can actually code for Android and it’s called programr.com. This enables you to get on right with Android programming without ever having to learn to setup and local Android environment. It’s a good place to start and there’s probably a monthly fee in order for you to use it.

So why have an Android tutorial?

Our website’s motto is: learning the web. Note too that the motto is always speaking in presence tense. And this graph will explain why:

So although we started as a WordPress website tutorial, we decided not to stop there becuase the web continues to evolve. In one of our post, we have shown how WordPress continues to grow as the most popular CMS platform on the web. And this is the main reason why we have our WordPress tutorial in order to help you build your own website. And as the graph above shows, Android is just too hot a technology to ignore. We were then confronted with the question on how to bridge the gap between WordPress and Android. But this is getting ahead of the story. Most important thing now is to get that Android development up and running.