Mobile developers must mind target audience

Those coding for mobile devices should first decide whether they are catering to smartphones or entry-level devices in order to optimize the sites' experience, say developers.

Site developers targeting mobile devices should decide whether they are focusing on smartphones or entry-level phones, while being mindful of usability and device constraints across the board, developers say.

Ronnie Liew, senior technical director at R/GA in Singapore, said coders should watch out for aspects such as screen size dimensions, Internet connectivity, bandwidth limitations, the availability of third-party plugin support, and level of user interaction.

In an e-mail interview with ZDNet Asia, Liew said: "The worst thing you can do is to take a regular site and display it on the mobile browser." Developers should redesign their sites and optimize them for the smaller dimensions of phone screens, he said.

Restrictions on the device's capabilities are another point to note, he said. Device users may not always have data access, so Liew suggested tapping the device's local storage to keep a Web app or site functional when the user is underground or in a plane.

A related concern would be bandwidth restrictions. A site heavy on graphics would take a toll on users who do not have unlimited data plans, as well as blunt the site's performance by prolonging loading times, he said.

The redesign of the site, besides aesthetics, also needs to take into account the differences between the way users interact with the site on a desktop and on a mobile device, he said, naming mouse hovering as an example. While a desktop user can hover over an item with the mouse to reveal more information, this is not possible with a touch-screen which requires the user to tap on an item, he explained.

Another developer, Andy Croll, said sites should be made simpler, both in their formatting as well as use cases.

Providing a useful subset of the desktop version's functionality is a good option, he said, pointing to the Guardian's mobile Web site as an example.

Developers should also take into account the form factor of various mobile devices, such as whether a numeric keypad would be used or a touchscreen, added Croll.

Liew reiterated that all this boils down to the target mobile platform for developers: "If the site is meant for devices like the iPhone, iPad or Android, performance would be key. But if the target platform is feature phones, then the lowest common denominator would be the way to go."

As such, site masters should also keep an eye on the amount of heavy lifting needed to be done by the phone, especially if they are lower-end handsets, said Liew.

Both developers mentioned Webkit-based browsers as a common target for developers. Smartphones such as the iPhone, Android devices, Palm Pre, Nokia's S60 handsets and--recently--BlackBerrys come with Webkit browsers.

According to StatCounter figures, Webkit's market share has been hovering above the 50 percent mark for the past two years.

An Adobe executive said earlier this month that mobile developers still have to contend with the issue of browser fragmentation due to different implementations by the various device makers.

As such, this makes it difficult to code for a common apps layer running across various mobile browsers, and developers have had to focus on individual browsers, a German developer said in an earlier interview on the topic.