Facebook engineer reveals HTML5 flaws

Facebook software engineer Tobie Langel, who's also the company's W3C AC representative, has posted online about the performance issues the company encountered while building for the mobile web. This follows Facebook CEO Mark Zuckerberg's recent statement that betting so heavily on HTML5 was "the biggest strategic mistake" that that company has made.

Langel outlined a number of key areas in which development for the mobile web fell short – at least as far as Facebook was concerned. He said that a "lack of tooling in mobile browsers makes it very difficult to dig down and find out what the real issues are", especially when related to memory complications Facebook often came up against, owing to the size of the service's content. "It's not uncommon for our application to exhaust the hardware capabilities of the device, causing crashes [and] it's difficult for us to understand exactly what's causing these issues," he added, hoping for better on-device or remote-access dev tools in the future.

Scrolling performance was also a big issue for Facebook, which Langel said was typically problematic on infinite scrolling feeds that would end up with large amounts of content. He noted there were technical problems – stuttering and GPU buffer exhaustion – but also said there were snags relating to how each device works: "Native momentum scrolling has a different feel across operating systems. [JavaScript] implementation [ends] up being tailored for one OS and feels wrong on other ones."

Additionally, Langel said the GPU is a "black-box with a clunky API to add things to it", and that he thinks we won't "get to a place where managing [the] GPU can be left strictly to the browser in a reasonable amount of time", along with arguing that standards require better touch-tracking support, smoother animations and improved caching. He also made plenty of suggestions regarding API development. Yet even given this rather high-profile negative experience regarding HTML5, developers aren't concerned about the technology's future nor its chances long-term versus native apps. "HTML5, or some derivation of it, will come out ahead in the end simply because having many competing UI language systems is counterproductive," argued Zurb partner Jonathan Smiley. "Devices are more and more quickly connected every day, and terminals that hold everything locally are finally starting to fade away. Apps won't be any different."