Facebook Plans to Speed Up its iPhone App | Hacker News Reader

Facebook Plans to Speed Up its iPhone App

bits.blogs.nytimes.com

60 pointsnicholassmith11 comments

Same link, discussion from earlier today: http://news.ycombinator.com/item?id=4167721

As primarily a web developer, it saddens me how much truth there is to this statement from the article:

The current version of the app is essentially an Objective-C shell with a Web browser inside. When it comes to speed, this is like putting the engine of a Smart Car in the body of a Ferrari.

Half the problem was HTML5 being slow.

But a lot of it was the fact their HTML5 views were not well cached, used XML and a mix of other formats for data interchange, and in fact were generally poorly made.

In short: their caching blows giant monkey balls. It regularly loses the like icon, or even the stylesheet entirely. But still manages to cache the wrong profile icon for the wrong person.

can someone tell me why HTML view apps are that slow on iPhone? I thought with all the money and time that has gone into the development of Webkit and Nitro (the JS engine?) we would be up to the speed of native now. Is this a rendering issue or just lack of bandwidth?

Well, for one, when you're embedding UIWebViews in your own app, the JS engine disables JITting to native code.

Apple will not sign and grant 3rd party apps write+execute memory permissions, making it impossible to build a JITter. So only "MobileSafari.app" get "native javascript performance".

Other than JS performance being downgraded when the app is built this way. It appears that the actual facebook servers that serve the customised content are also slower (read: much slower.)

The speed experienced can't be attributed to JS alone, there simply isn't enough JS being processed when many of the 'slow' encounters are being felt, additionally the speed fluctuates through the day/week which would be consistent with server load rather than a small JS not loading and running quickly enough.

Proof? Is it slower simply because they have to deliver more information (rendered UI in the form of html as opposed to json)?

I've heard from Android users that their app (which uses the same techniques) is quite bad as well. A lot of my friends just use the mobile site through their Android phone's web browser.

Yes it's just as bad on my iPhone 4 as it is on my GNex. On Android I typically use a 3rd party client like Flipster (https://play.google.com/store/apps/details?id=com.flipster&#...). I think it's available for iOS as well but I haven't tried it on there (typically only used for development).

Nitro is disabled in UIWebviews due to security concerns.

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