HTML5 and the Mobile Web

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(For more resources on this topic, see here.)

Introduction

Both HTML5 and mobile web are promising technologies. Both have relatively short histories. In this article, most topics we will be covering are relatively basic. This is to help you get started with mobile development quickly and with minimum effort.
Both mobile and HTML5 are still evolving in nature and there could be many questions in your mind. We will clear those doubts and set your mind focused on things that matter. The mobile web is growing fast. We now have mobile Safari which is one of the most used apps on the iPhone, allowing developers to build high performance web applications and enhancing users’ browsing experience. You do not need a developer account to host and run a mobile site, you don’t need to get approval from any app market to launch a mobile website and you can make updates any time you like without the hassle of waiting for approval. All these are benefits of mobile web development, but at the same time, there are challenges such as inconsistencies among browsers, the lack of certain features compared to native apps, and security. We can’t tackle them all, but we sure can solve some of them. And we will see, when developing a mobile site, how we can separate the common practices from the best practices.
There are literally thousands of smartphones out there; you don’t need every single one of them to test your application on. In fact, you may need fewer than 10. If that’s still out of your budget, then two devices are good enough. For the rest, you can use simulators/emulators to do the job. This book focuses on six A-grade mobile devices, with focus specifically on iPhone, Android, and Windows Phone:

  • iOS
  • Android
  • Windows Mobile
  • Blackberry v6.0 and above
  • Symbian 60
  • Palm webOS

There are two browsers that are device-independent that will also be covered in this book. They are:

  • Opera Mobile
  • Firefox Mobile

Just because other browsers are not in the list does not mean they won’t be covered by the issues and techniques we discuss in this book.


Identifying your target mobile devices

Target browser: all
You can’t possibly make a mobile site for every single mobile device. No one has the time or energy to do so.
Cross-browser mobile web development can be crazy. It’s hard to define the scope of the work, as John Resig (creator of jQuery Mobile) pointed out in his presentation slide describing his experience building jQuery Mobile (http://www.slideshare.net/jeresig/testing-mobile-javascript), he asked three questions:

  • Which platforms and browsers are popular?
  • Which browsers are capable of supporting modern scripting?
  • What devices and simulators do I acquire to test with?

When you are building a mobile site, you have to ask yourself similar questions, but not the exact same questions, because remember your site should be specifically tailored to your target audience. So your questions should be:

  • Which platforms and browsers are most commonly used by visitors on my website?
  • How many people access my website from a mobile device that is capable of supporting modern scripting?
  • Which devices and simulators do I need for testing?

Which platforms and browsers are most commonly used by visitors on my website?

Now let’s answer the first question. Before building a mobile website, you must first find out who are your target audience, and what mobile devices they use when visiting your site. There are many analytics tools that can help you answer these questions. One of those is Google Analytics. You can sign up for a free Google Analytics account at: http://www.google.com/analytics/.
The way to do it is fairly straightforward: most developers are no strangers to Google Analytics. All you have to do is to include the JavaScript snippet from the the Google Analytics site and embed it in your web pages.
JavaScript can be rendered in most modern smartphones, so there is really no difference between using it on a desktop site and on a mobile site.

How many people access my website from a mobile device that is capable of supporting modern scripting?

Now let’s answer the second question. One thing you may want to find out is the number of people using mobile browsers to surf your site. And you also want to find out how many people use a relic mobile browser that doesn’t support JavaScript at all. This is because if the percentage of people using low-end smartphones is higher than that of people using high-end smartphones, it may not be worthwhile using HTML5 in the first place (although the chance of this is very low). So if your goal is not just to know the number of people using smartphones, but also the number of people who use older versions of mobile phones, Google Analytics for mobile comes to the rescue. You can download the script from:
http://code.google.com/mobile/analytics/download.html#Download_the_Google_Analytics_server_side_package

Google Analytics for mobile server-side packages currently supports JSP, ASPX, Perl, and PHP. Let’s take a look at one of the examples in PHP. All you have to do is to change the ACCOUNT ID GOES HERE with your GA account ID. But remember to replace ‘UA-xx’ with ‘MO-xx’.
Unfortunately, when you use the server-side version, you can’t use it on pages where you also use the standard JavaScript tracking code, ga.js. Using the server-side version means that you have to give up the JavaScript version. It can be annoying because the JavaScript version provides a lot of dynamic tracking mechanisms that are lacking in the server-side version:

<?php
  //  Copyright 2009 Google Inc.
All Rights Reserved.
  $GA_ACCOUNT = “ACCOUNT ID GOES HERE”;
  $GA_PIXEL = “ga.php”;

  function googleAnalyticsGetImageUrl() {
    global $GA_ACCOUNT, $GA_PIXEL;
    $url = “”;
    $url .= $GA_PIXEL . “?”;
    $url .= “utmac=” . $GA_ACCOUNT;
    $url .= “&utmn=” . rand(0, 0x7fffffff);

    $referer = $_SERVER[“HTTP_REFERER”];
    $query = $_SERVER[“QUERY_STRING”];
    $path = $_SERVER[“REQUEST_URI”];

    if (empty($referer)) {
      $referer = “-“;
    }
    $url .= “&utmr=” . urlencode($referer);

    if (!empty($path)) {
      $url .= “&utmp=” . urlencode($path);
    }

    $url .= “&guid=ON”;

    return $url;
  }
?>


Alternatives to Google Analytics

Google Analytics is not the only mobile analytics service in the market. There are other services providing more specialized services. For example, PercentMobile is a hosted mobile analytics service that makes your mobile audience and opportunities clear. You can find out more about this service at:

http://percentmobile.com/

Accuracy of Google Analytics

The location reported by mobile devices may not always be accurate; Google Analytics uses IP addresses to determine user location for Map Overlay reports. They are subject to possible inaccuracy, as mobile IPs originate from the wireless carrier gateway which is not necessarily co-located with mobile users.

Server loading speed concern

Due to the server-side processing, some additional server load may be incurred. Google recommends you first test the snippet on a few of your pages to ensure all is well before rolling out to an entire site.

Setting up mobile development tools

Target browser: all
Now one question still remains unanswered from the previous recipe: which devices and simulators do I need for testing? We will find this out in this article.
If you have figured out what major mobile devices you are going to support, now is the time to see how to set them up. Mobile development can be costly if you test on various mobile devices. Although we have all these mobile simulators and emulators available for testing, it’s not as good as testing on a real device. Now let’s see how we can maximize the testing coverage and minimize the cost.

Getting ready

We are going to make some assumptions here. Each case is different, but the idea is the same. Let’s assume you have a Windows operating system on your desktop, but the top visitors to your site surf using iOS, Android, and Blackberry.

How to do it…

Your goal is to maximize the coverage and minimize the cost. All three devices have emulators, but not all support different platforms.

Name

Compatibility

iOS simulator

Mac

Android emulator

Windows, Mac, Linux

Blackberry simulator

Windows

As you can see, since iOS simulator only works for Mac, and if you are running a Windows OS, the best and only choice is to purchase an iPhone for testing. For Android and Blackberry, because they both have emulators for Windows, to save budget, you can download the emulators.

How it works…

  1. List the top mobile devices people use to surf your site.
  2. Know the machine OS you are using for the development.
  3. Find out the compatibility of each of these device emulators to your development environment.

There’s more…

If you have the budget for more than one mobile device having a different OS, you can think further about screen sizes and the DPI of the mobile device. You may not need to buy two high-end devices. For instance, it’s not necessary to own an iPhone4 and an Android Thunderbolt. You can buy a lower-end of Android just to test out how your site would look on a lower-end device. So the idea is to combine your OS, mobile devices, and emulators to maximize the scenarios to cover.

Device simulator/emulator download lookup table

The following table shows a list of popular mobile device emulators for mobile web design and development testing:

Name

Type

Compatibility

URL

iOS

Simulator

Mac

https://developer.apple.com/devcenter/ios/index.action#downloads

Android

Emulator

Mac, Win, Linux

http://developer.android.com/sdk/index.html

HP webOS

Virtual Machine

Mac, Win, Linux

http://developer.palm.com/index.php?option=com_content&view=article&id=1788&Itemid=55

Nokia Symbian

Emulator

Win

http://www.forum.nokia.com/info/sw.nokia.com/id/ec866fab-4b76-49f6-b5a5-af0631419e9c/S60_All_in_One_SDKs.html

Blackberry

Emulator

Win

http://us.blackberry.com/developers/resources/simulators.jsp

Windows Mobile 7

Emulator

Win

http://www.microsoft.com/downloads/en/details.aspx?FamilyID=04704acf-a63a-4f97-952c-8b51b34b00ce

Browser simulator/emulator download lookup table

Apart from device testing tools, we also have tools for platform-independent browsers, notably Opera and Firefox. These are shown in the table below:

Name

Type

Compatibility

URL

Opera Mobile

Emulator

Mac, Win, Linux

http://www.opera.com/developer/tools/

Opera Mini

Simulator

Mac, Win, Linux

http://www.opera.com/developer/tools/http://www.opera.com/mobile/demo/

Firefox for Mobile

Simulator

Mac, Win, Linux

http://www.mozilla.com/en-US/mobile/download/

Remote testing

Apart from emulators and simulators, there are also test frameworks that give you remote access to REAL devices. One of those tools is DeviceAnywhere; one problem is that it is not free.
http://www.deviceanywhere.com/

BlackBerry simulator

Target Browser: BlackBerry
Most mobile device simulators are easy to install and configure if you follow the instructions on their sites, but BlackBerry simulators work differently from other mobile device simulators. For Blackberry device simulators, to connect to Internet, besides downloading the simulators, you also need to download and install BlackBerry Email and MDS Services Simulator.

Getting ready

Make sure you have chosen a simulator to download from:
http://us.blackberry.com/developers/resources/simulators.jsp

How to do it…

First, go to the page: https://swdownloads.blackberry.com/Downloads/entry.do?code=A8BAA56554F96369AB93E4F3BB068C22&CPID=OTCSOFTWAREDOWNLOADS&cp=OTC-SOFTWAREDOWNLOADS. There you will see a list of products similar to the following screenshot:

Now select BlackBerry Email and MDS Services Simulator Package and then click on Next.
After downloading and installing the software, you must first launch the service simulator before the Blackberry simulator, in order to allow it to connect to the Internet.
The following is a screenshot of a Blackberry simulator:

Setting up the mobile development environment

Target browser: all
Before we start mobile web development, we have to first set up a development environment.

Getting ready

  1. Set up localhost on your machine. For Windows, Mac, or Linux, the easiest way to set it up is to use the popular and free XAMPP software: (http://www.apachefriends.org/en/index.html).
  2. Make sure you have a wireless connection.
  3. Also you should have a mobile device with you. Otherwise, use a mobile simulator/emulator.
  4. Ensure your mobile device and your desktop are on the same wireless network.

How to do it…

  1. Create an HTML file and name it ch01r1.html at the root directory of your localhost:
    Inside ch01r01.html, type in the following:

    <html>
      <head>
      <meta name=”viewport” content=”width=device-width,
    initial-scale=1.0″>
      </head>
      <body>
        <header>
        Main Navigation here
        </header>
      body content here
        <footer>
        Footer links here
        </footer>
      </body>
    </html>

    
    
  2. Now get your IP address. If you are using Windows, you can type the following line in your command prompt:

    ipconfig

    
    
  3. Once you have got your IP address, (for example, 192.168.1.16.), enter it in your mobile browser URL address bar. Now you should see the page load with the text displayed:

How it works…

Within the same network, your mobile device can access your desktop host through your desktop IP address.

There’s more…

If you don’t have a mobile device, you can use one of the simulators for testing. But it’s recommended to have at least one or two real mobile devices for testing. A simulator could test most things, but not everything, accurately.

Testing on a Safari desktop

If your main target audience is iPhone mobile Safari users, you can also do testing on a desktop to save time. To do so, open up Safari, go to Preferences, click on the Advanced tab, check Show Develop menu bar as shown next:

Now click on the display menu for the current page, choose Develop | User Agent | Mobile Safari 3.1.3 – iPhone:

List of community-based collection of emulators/simulators

There is a list of emulators and simulators available if you really don’t have a Smartphone at hand. You can find the list on a wiki on the Mobile Boilerplate project:
https://github.com/h5bp/mobile-boilerplate/wiki/Mobile-Emulators-&-Simulators

List of emulators/simulators collection by Firtman

Maximiliano Firtman, a mobile and web developer, also an author, maintains a list of emulators on his site at:
http://www.mobilexweb.com/emulators

Using HTML5 on the mobile web

Target browser: all
Now we are going to create a simple HTML5 page for your mobile device. If you already have experience with older versions of HTML, HTML5 should be easy to understand. And if you have made a web page for desktop before, it won’t be hard for you to make one for a mobile device.

Getting ready

Create a new file ch01e2.html.

How to do it…

Save the following code in the file:

<!doctype html>
<html>
  <head>
  <meta name=”viewport” content=”width=device-width,
initial-scale=1.0″>
  </head>
  <body>
    hello to the HTML5 world!
  </body>
</html>


Now render this in your mobile browser, and you should see the text render just as expected.

How it works…

As you can see, the only difference between HTML5 and other HTML pages is the Document Type Definition (DTD) we used: <!doctype html>.
You might have seen the code <meta name=”viewport” content=”width=devicewidth, initial-scale=1.0″> and are wondering what it does. It helps Mobile Safari to know that the page is as wide as the device. Setting initial-scale=1 tells the browser not to zoom in or out.

There’s more…

Here’s a little bit of history of HTML5: there are two versions of HTML5 draft, one created by W3C and the other by WHATWG. The W3C is run by a group that is democratic in nature, but super slow in practice. WHATWG is edited by one person, Ian Hickson (who is also working for Google), and a group of people who are not public. As Ian does most of the decision making, it makes WHATWG’s version progress faster.

HTML5 and version number

You might be wondering why HTML5 is being so ambiguous by using a declaration without even a version number. Well there are many reasons to justify this:

  1. Version support of HTML doesn’t matter much to browsers. What matters is the feature support. In other words, if the browser supports the HTML5 feature you are using, even if you declare the document as HTML4, it will still render the HTML5 element as expected.
  2. It’s easier to type!

Mobile doctypes

One question you may ask is whether it is safe to use the HTML5 DTD <!doctype html>. The answer is DTDs were made for validation, not browser rendering. Your next question might be: what about quirks mode? <!doctype html> is the minimum information required to ensure that a browser renders in standards mode. So you are pretty safe to use <!doctype html>. You may have noticed that we use <!doctype html> instead of <!DOCTYPE html>. The reason is HTML5 is not case sensitive, but for consistency with other HTML tags, we will use lowercase throughout the book.

Free resources to learn HTML5

There are many excellent and free books, and articles about basic HTML5 tags. If you are unfamiliar with HTML5, you can check out one of the following:

If you are the kind of person who really wants to know every detail about something, you can read the official HTML5 specs.
The W3C version of the spec is at:
http://dev.w3.org/html5/spec/Overview.html
The WHATWG version of HTML Living Standard is at:
http://www.whatwg.org/specs/web-apps/current-work/multipage/

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