Chapter 14. I See HTTP

Stoyan Stefanov

Ladies and gentlemen, boys and girls. Say hello to icy.


It’s an iOS app that lets you debug HTTP. It’s like HTTPWatch ( or WebPagetest (, but for mobile. Like’s mobitest (, but in your pocket, it works with 3G, Edge (as these can have different characteristics and carrier optimizations than WiFi), and also lets you inspect pages behind login.

Some details

  • It’s a UIWebView that loads the page you want and provides a NSURLCache class, which logs whatever the iOS networking layer throws at it.

  • It’s on github ( Note that this is my very first attempt at iOS and Obj-C so the code quality is probably atrocious. License is public domain, because I don’t really understand the others.

  • The name is icy, because it’s iOS and it’s the law that app names be prefixed with an “i”. Also (to my Eastern European ear at least), “icy” sounds like “I see” (spelled “ic” in chats) and is the beginning of (said with spookiest of voices) “I see… HTTPeee.”


A journey of a thousands miles begins with a single tap. As you can see in Figure 14-1, the icon is the default/missing icon. (Who cares about icons?) If you focus hard enough you may convince yourself that the white icon actually makes sense, it’s like snow, or, there you have it, ice.

App icon

Figure 14-1. App ...

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