The controversy swells on Nitro, the JavaScript engine found in Safari Mobile from iOS 4.3. Earlier this week, we noticed that the web app were 2 to 2.5 times slower than the same site displayed in Safari.
Shortly after a study by Blaze Software said loud and clear that a Nexus S averaged 52% faster than a 4 iPhone to surf the web. However, this study was not conducted directly through Safari, but in a WebView.
These various data have not failed to create a little controversy, which once will not hurt, drove Apple to break the silence. One of his spokesmen, Trudy Miller, confirmed that the web views do not include all optimizations for Safari. Therefore, the study of Blaze Software is partly inaccurate. It is true that the iPhone's browser is slower than that of Android. By cons, running web app (thus bypassing the browser) is actually much faster on Android.
So why web apps are they deprived of Nitro and the lack of support for the HTML5 cache? For John Gruber, we must not see evil everywhere and think that the way the Californian Company focuses on native applications to web applications.
The real problem for Apple is safety. Unlike its predecessors, Nitro is a JavaScript engine that includes the time compilation (JIT). However, a JT needs to have the ability to mark pages in RAM memory as executable. However, unlike Mac OS X, Apple iOS prohibited on grounds of safety. Such a mechanism could lead to hijacked the execution of unsigned code.
In other words, if Safari 4.3 is under iOS much faster, there is a significant part-cons: if someone manages to exploit a vulnerability in its browser, then it can do much more damage than before. One can imagine that Apple has enough confidence in its browser to integrate such a possibility.
For Gruber, it is more likely that Apple will not stop there. He believes that to generalize Nitro web applications, there should be a web application to run JavaScript in a process separate and independent, a bit like Safari on Mac and PC that creates a separate process for Flash. In theory, this is what Apple is preparing for Webkit 2, whose project was announced last April: "WebKit2 is designed primarily to support the separate processes, where the Web content (JavaScript, HTML, etc.). made his living in a separate process [...] this model is comparable to Google Chrome, the chief dissimilarity that we have built straight into the structure, and it is easy to get to other browsers.
