This week’s reading list is devoted to Device Detection vs Responsive Web Design.
With all the cool kids getting into RWD these days, it’s time to have a look at the Device Detection companies again. Device Detection is the practice of matching a device’s UA string against a table of such strings and looking up certain characteristics of that device and then serving different websites accordingly.
Mike Taylor, an ex-colleague of mine at Opera, now at Mozilla (and pathological hater of chickens) set up a collaborative document to collect use cases that people are trying to solve with UA detection (which can’t be solved by feature-detection), which is summarised by Karl Dubost (ex-Opera, now Mozilla) in User Agent Detection Use Cases.
Those who oppose Device Detection do so for philosophical reasons – it’s one web and we shouldn’t serve different content to different devices or browsers, or they are certain browser vendors: Internet Explorer, Firefox OS and Opera all have reasons to dislike browser sniffing or device detection (“this website is only available to iPad users”). Google uses device detection all the time on its properties, as do many other large companies.
The device detection companies have begun to issue reports comparing their products with responsive, client-side techniques. Here are three that I’ve seen this week:
- 24.com Case Study (51Degrees)
- Responsive Images Specification and Real-World Scenarios (scientamobile)
- M-commerce insights: Mobile users and context mobiForge – published by dotMobi, who sell DeviceAtlas.
They’re worth reading. Of course, case studies only go so far; every business, territory and site is different. One thing everyone agrees on is that performance matters – slow sites lead to fewer conversions. mobiForge has an article M-commerce insights: Give users what they want, and make it fast that claims
RWD sites were the slowest, on average, to load on mobile – 8.4 seconds – while dedicated mobile sites loaded fastest – in 2.9 seconds. Non-responsive desktop sites took 6.57 seconds to load.
I’d like to see proper A/B testing: a well-made responsive version of a site versus its “m-dot” equivalent, redirected from its canonical URL and assembled after a device look-up, across a variety of devices and network conditions. If we’re going to argue, it might as well be about data.
Update 1 Dec 2014: Here’s some initial research on the top 1,000 mobile websites: M dot or RWD. Which is faster? that concludes that “m dot” sites are 50% slower for time to first byte, and
RWD sites are VERY competitive on Visually Complete and SpeedIndex scores. The median values are within 5% for both metrics. Even though it appears that RWD is faster, there is enough fluctuation in the data that we should probably call it a dead heat.