Bloated website code drains your smartphone's battery

Regular smartphone users know that watching a video or playing a game can quickly drain the battery, and we recently learnt that free apps are also power hungry, but even simple web browsing has an energy cost. Now, researchers at Stanford University and Deutsche Telekom have discovered that many popular sites, such Wikipedia, IMDB and even iPhone manufacturer Apple's homepage, are wasting energy due to bloated code.

The researchers have also shown how to reduce this energy usage by almost 30 per cent, without affecting user experience. Stanford computer scientist Narendran Thiagarajan and colleagues used an Android phone hooked up to a multimeter to measure the energy used in downloading and rendering 25 popular websites. The team then repeated the measurements with locally saved versions of the website, allowing them to separate out the energy required to render a page from that need to download it. Most modern websites use Javascript and CSS files to provide additional functions and styles that aren't possible using basic HTML, but the researchers discovered that many of the websites they looked at were loading large files that weren't being used in the page.