This article gives an objective view of the advantages and disadvantages of using WAP in the development of mobile Learning (mLearning) training course material.
The usage of mobile phones is widespread and more extensive than personal computers or laptops. The ease of use, mobility and personalisation aspects of mobile devices makes it an ideal medium for this next step in distance learning.
Advantages of using WAP
Transporting data in the mobile networks of today, for example GSM, has been compared to 'Carrying an ice cube in a plastic bag in the desert heat of 40C'. The conditions of the mobile network are harsh. Hence, given these harsh conditions, it is essential to select an appropriate application environment and design the application for the mobile user and the challenges provided by the mobile network.
The mobile network is different, the bandwidth is narrow, and delays are greater than in the PC /Wired network which supports 2 Mbits per second. The mobile network in comparison provides resources of 9.6kbps for a user.
The challenges for developing an application for the mobile environment are mainly these obvious differences between the Mobile network and the Wired environment.
A mobile handheld device e.g. Mobile Phone or Smart phone is different to a PC/ Laptop. The screen size is small, the number of keys a user has access to is limited to 16 keys or less. The device also is limiting is memory storage, processing power and battery power.
The WAP protocol is designed with the network, device and user interface limitations in mind. This means that WAP is optimised for mobile networks with narrow bandwidths, mobile devices with small screens and limited keys for user entry, little memory storage, and limited processing and battery power.
This makes WAP an ideal choice for developing an application for the mobile network. But any ideal in practice has pros and cons. Thus, this paper will further describe these advantages and give an insight into the limitations or disadvantages.
Data supporting WAP
Today there are more than 50 million mobile handsets that are WAP enabled. It is expected that all mobile handsets will be WAP enabled by the end of 2001. It is also predicted that by 2003/ 2004 there will be 1 billion handsets in the world.
Key players in Mobile Internet market support WAP. These include the Network Operators, Hardware Manufacturers, and Software Application Developers.
All the major handset manufacturers are committed to WAP and future mobile devices will support multiple technologies including WAP, GPRS and Bluetooth. As 3G (WCDMA, UMTS).is launched WAP will also evolve for these future networks.
Network operators are behind WAP and their support is clearly demonstrated by the deployment of WAP world-wide. There are more than 200 Operators that have WAP applications and services available to their customers. This is a huge investment in infrastructure, equipment and software applications and services.
Thousands of software application developers have been behind WAP and have created the applications and services for WAP. This commitment to WAP is clearly shown by the many thousands of WAP sites available in the word today.
Features of WAP (Personalisation and WTA)
When comparing the mobile network to the fixed network there seems to be many limitations, as already discussed. The mobile network also provides unique advantages or features such as the position or location of the device and personalisation (both user preferences and device capabilities).
The WAP language supports these features of Positioning and Personalisation. A WAP language component supports User Profiles which contains information on the user preferences and the device capabilities.
In addition, Telephony Integration is provided by the the Wireless Telephony Application, or WTA component. This allows a developer to easily integrate a telephone call in any WAP application. Thus the user can select a link e.g. Make Call to call a number from the application rather than exit the application and enter the telephone number
Optimisation of WAP languages
WML is Wireless Markup Language. It is based on HTML, but is optimised for mobile networks and small handheld devices. WML is used to create static content such as text to be displayed on the screen of the mobile device. WML, like HTML is a tagged based browsing language. However, WML has a limited number of tags and because of the limitations discussed earlier, these tags are sufficient for the purposes of creating mobile internet applications.
WML allows the developer to create the user interface which will be displayed on the screen of the mobile device. WML is straightforward and an easy to learn markup language. The type of content displayed on the mobile device screen such as text, links, images, data entry fields and selection lists are all easily created by the developer using the appropriate WML tag.
WML Script also provides the developer with access to standard libraries which offers re-use and efficient code. These libraries contain functions that are already coded, that can be called from WML or WML Script. They include conversion of string types, browser access and dialog access directly from WML Script.
The WAP languages, WML and WMLScript are supported by the WTA (Wireless Telephony Application) Libraries. These public libraries allow the use to build into the application easy access to telephony functionality. This telephony integration means that the user can select a link e.g. Call Tutor to contact the tutor from the application rather than exit the application and enter the telephone number.
The efficiency of WML and WML Script is further enhanced by the binary encoding of the application sent over the Mobile Network. This means that a series of 0's and 1's is sent instead of text. This makes it very efficient over a narrow bandwidth.
Limitations of using WAP
The main limitations of WAP today are related to the devices used and the mobile networks. The limiting factors of the device means that large amounts of data, especially graphics and animations are not recommended. Although, WAP supports images today only black and white images are possible. Colour Images and Animations will be supported in future releases of WAP.
Other limitations that the user perceives are not really WAP limitations but restrictions due to the mobile networks. Many users identify that WAP is slow and that it can take up to 2 minutes to access content Even with todays limitations it is possible to design applications well so that the best use of the scarce network resources are made. A well designed application can be accessed via WAP in less than 10 seconds.
The cost of using WAP is another disadvantage. The cost to upgrade to a WAP device and the additional cost to access content has limited WAP very much to the corporate user rather than the mass market.
However, these main limitations of WAP will soon be only challenges as the Speed of the networks are already increasing with the launch of GPRS, and in future the Third generation, 3G networks. Hopefully, GPRS will also address the Cost issue of WAP and bring down the cost of using WAP. This is promised as the user will be always connected but will only pay for the usage of sending / receiving data.
The application developer needs to consider the following three areas of limitations when designing applications for WAP.
The Bandwidth and Delay factors are the main network restrictions. For the optimisation of the application using WAP is an advantage, as WAP already takes these limitations into account. The developer, in addition, can design the application so that data to be sent over the mobile network is kept to a minimum. In the case of mLearning content, this can be achieved by structuring the content into useful pieces of information or snapshots. Summary type of information as opposed to pages and pages of text. Also images and graphics must be kept to a minimum or avoided as these take up a lot of memory usage on the devices.
Using the WAP design concept of 'Deck of Cards' encourages the developer to redesign the structure of mobile learning training material. A Card is the amount of data that will be displayed on the screen of the device, including any scrolling the user may do. A Deck consists of a number of Cards, that the Device will download from the mobile network. This is used appropriately can give a very positive user experience as navigating the cards is the deck is very fast, less than a second as the data is already stored on the device.
The user interface and the memory and processing power are the main limiting factors of the device. The developer can overcome these by ensuring that most user interaction is via the navigation of links. Thus the user can access different modules of the course and related information via an Index of Links. When the user needs to enter data, this can be handled by the Select Lists which allows the user to make a selection on a number of options rather than type in large amounts of data (not recommended for mobile phones).
All of the design principle talked about in the previous section are also relevant, as the conciseness of information and the 'Deck of Cards' structure will help render the course content on the small screens of the devices to the user's satisfaction.
The application developer needs to consider the user when designing the mlearning course content and structure.
The following simple principles are recommended:
- Keep it Simple
- Avoid large amounts of data
- Avoid underlined text as this will be mistaken for Links
- Use Selection Lists for data entry
- Consistency - place links in same place throughout application
- Always provide link to Start page or Index
- Use Titles on Cards to ease navigation
- Use Tabloid format - headlines and summaries
- Use short words
The only confirmation of usability is to test the application on sample users for ease of use, before the application is launched.
The main pedagogical issue to consider is the suitability of a course to the mLearning environment. Not all courses are suited to the mLearning environment. Purely technical and very practical courses are not suitable.
However, short courses and mainly theory and information type courses are suited to the mobile learning environment. The learning environment can be enhanced by the use of quizzes to test knowledge, summary of main learning points, and interaction with other students and the tutor via telephony integration.
In conclusion, WAP is suitable for the creation of mobile learning training course material. The optimisation of WAP and the handling of the design challenges makes it feasible to use mobile handheld devices for distance learning in real-time. The application developer must always be aware of the user and take into account the usability issues if the application is to be a success.