OER Handbook/educator/Compose/Mobile versions



Mobile devices include small computing devices, such as handheld computers, sub-laptops, mobile media players, and even cell phones. In many areas of world, access to mobile phones is more widespread than access to desktop computers. In addition, access to cell networks is more widely distributed than access to traditional Internet (via landlines, T1, or WiFi). Mobile devices have been found to be effective tools for learning and in many cases are easier to integrate into instruction. For all of these reasons, accessing OER via mobile devices is an important thing to consider.

Specific OER projects may or may not be well-suited for use on mobile devices, depending on how they were developed, how they are hosted, and a variety of other considerations.

Online vs. offline use
While most OER exist online, mobile users often prefer to download content and access it offline. Content can be provided offline in formats such as ebooks, word processing documents, or multimedia files. These files can then be stored on a memory card or on internal device memory. As an example, some universities distribute online courses for access on mobile devices. This course content can be downloaded on a desktop computer and then transferred to a memory card for offline use on a cell phone or handheld device like an iPod.

In order for OER to work in this way, developers need to make the content available in a downloadable format. Using XML or a similar system that tags content in a flexible way can make exporting content for various types of use feasible. See the discussion of file format issues below for more information.

The most common problem with mobile versions of an OER is device incompatibility. There is no way to test on all possible mobile devices. Therefore, you should focus on testing mobile devices that will be used by your target audience. Ideally all learners would be using the same mobile device, though that is rarely the case in practice.

Bandwidth requirements
When content is going to be streamed or viewed online, bandwidth is an important consideration. Mobile devices with Internet access often have relatively low connection speeds. This low connectivity results in longer download times, especially for multimedia content. One solution to this is to present content in smaller chunks that can be downloaded individually. Bandwidth requirements can also be reduced by shrinking or reducing images, breaking up pages of text, or re-encoding video for smaller file sizes. It is recommended that you try out your lesson using the available bandwidth before distributing it.

Device issues
Mobile devices come in a wide variety of sizes and with many operating systems and software programs. Keeping in mind the unique features of mobile devices is important if OER content is to be usable.

Display size
Display size is one consideration. Most mobile devices have a relatively small screen size (e.g. 320 x 240 pixels). While often a concern, research has shown that readability and comprehension are not affected by small screen sizes. Anecdotal observation of learners with mobile devices confirms this (Fasimpaur, 2003).

Simple text is generally not adversely affected by screen size, because the text will reflow to fit the screen. However, images, video, and text that is highly formatted can be rendered unusable on small screens. Design suggestions to maximize usability include avoiding tables, frames, and columns; providing low resolution version of images; including text alternatives for images; and avoiding pop-ups and Flash. (These suggestions will also increase accessibility for persons with disabilities as well; see Use Accessibility in Use OER for more details.)

Content creators who want their content to be accessible to mobile users may wish to consider providing a mobile version of their site, as done by Wikipedia and others. Again, using XML and content-based tags will make compiling multiple versions like this easier.

File format
Another issue to consider is file format (see File Format section for a list of formats). Some mobile devices have browsers that can read standard HTML files (see below), but for offline viewing or multimedia files, other file formats should be considered. While many proponents of OER favor "open" file formats, at present, most mobile devices do not support these formats. Ideally, content providers will offer options for different users.

For text-based information, simple text, RTF, or HTML files are widely accessible formats. Formats such as DOC (MS Word), ODT (Open Office), or PDFs should be avoided if possible, since they are not widely available on mobile devices. For many handhelds, ebooks are a favorable format since they provide extra features like hyperlinks, linked dictionaries, and even text to speech capabilities. However, to provide ebooks, a developer must know the software available for the target users' devices. (There are many different ebook programs.) Mobipocket is one of the most widely used ebook readers, because it supports many devices. Microsoft Reader is another commonly used ebook format, but is not as broadly compatible. (Note: These are both free, but not open, tools.)

For audio content, MP3 is the obvious choice for file format. While this is not strictly speaking an open format, it is a format that will play on nearly every device that plays audio. (The open alternative is OGG, which is supported on very few devices.)

For video content, there is currently not one format that works on most mobile devices. The options for content providers are to provide video content in multiple formats or to suggest that users convert to the video to their own format of choice.

Browser capability for online content
For online content, it is important to remember that mobile device browsers vary in their capabilities. Often items like Javascript, Flash, or other types of interactive features will not work properly on mobile devices. Frames and tables also do not display well on small screen browsers.

Technical support for learners
In order for OER to be successful on mobile devices, learners must be familiar with their device, the device capabilities, and how to access and use content available via the device. This may involve delivering training and technical support to make sure learners can effectively use the tools.