Bruce Lawson on Device Detection

An interesting thread has opened up on the blog of Opera's Bruce Lawson. Bruce recently wrote an article putting together his thoughts on device detection and RWD. In his blog, (perhaps somewhat mischievously) entitled Device Detection vs Responsive Web Design, Bruce recaps that RWD is now a widespread approach to web design and then takes us on a quick overview of the relative merits of using server-side device libraries either alongside that approach or instead of it. He highlights the following requirements of a good device detection solution:

• The need to be comprehensive
• The need to be up-to-date
• The need to be accurate

Well so far so good, we are confident that DeviceAtlas leads not just on those metrics but several others such as transparency, server efficiency and speed.

Bruce also argues that good device detection solutions are "an order of magnitude" more reliable than CMS plugins, or JavaScripts for various reasons:

• JavaScript inability to indicate if a device is touchscreen or the physical dimensions of a screen
• Regex scripts that recocognize IE11 as IE1, or worse don't know Chrome exists

Bruce points out that device detection opponents' objections are philosophically based. Specifically he mentions the "one web" advocates who want no distinction between content served to different devices and browser vendors, whose objections are perhaps less about philosophy than the exigencies of the browser business.

Bruce has written and commented widely on issues pertaining to mobile and web, both in and out of his role as evangelist for Opera, so we respect his opinion. But we do feel the whole RWD vs Device Detection debate is something of a false dichotomy. Articles like M-commerce insights: Mobile users and context on mobiForge are intended to show exactly that: business requirements, territories and site goals are different. It's not just about performance and speed although undoubtedly a factor. If and how much you want to optimize separately for a particular device category are also key considerations.

The comments thread in the article does a good job of showing that its more a case of "horses for courses" than a black and white debate, so worth repinning some of them here:

I’ve advocated previously (hah, having flashbacks to my preso from 2012 Adapt and respond) that having a separate site is still a viable choice. It’s simply another tool/option. Also, it’s not necessarily a binary decision: even once you do stuff based on browser detection server-side, including moving the user to another subdomain, you should still use responsive techniques. And of course offer the user a way to get back to the “non-mobile-or-whatever-your-script-decided” version. 
Patrick H. Lauke

Device detection is often characterised as a kind of restriction or artificial barrier. It may have been in the past but these days server side adaptation is used to deliver an improved experience. Companies like Google use it because it enhances their ability to serve their customers, in all territories, on all devices. Like how Google slighly adjusts line heights on your tablet to make targets easier to tap? It really helps. When you download Opera you’re automatically directed to the right download link. That helps too. Yes, not all companies do it well and mistakes are made but overwhelmingly, server-side detection is used to serve visitors, not hinder them.

The one web concept is hardly meant to be taken literally. It’s worth remembering what TBL said on the subject in the HTTP 1.0 spec in RFC1945, section 10.15 (emphasis mine):

The User-Agent request-header field contains information about the user agent originating the request. This is for statistical purposes, the tracing of protocol violations, and automated recognition of useragents for the sake of tailoring responses to avoid particular user agent limitations. 
Ronan Cremin

I’m using device detection for RESS on an m-commerce site and am able to to compare conversion with a design which only has responsive, but I’m not able to share the results.

I’d encourage people to be open minded and test, you’re spot on to raise this. Stephen

For the full list of comments, including the opposite view, head over to Bruce's site.