It’s no secret that “multitasking” is one of the great new features of iOS 4. Unfortunately, many people have a misconception about what Apple has implemented. Hopefully this short essay will help you understand the restrictions and the good reasons for having these limits.
On your desktop, multitasking means that any application or process can run [...]
I’ve always wondered what it would be like to write a book. Now I know. It’s the hardest thing I’ve ever done, but rewarding beyond words.
For those of you asking for PDF or Ebook editions, you can order them now directly from O’Reilly. The printed version will be available in a couple of weeks. The [...]
It’s been a little over 2½ years since I last looked at the performance of Apple’s mobile devices. A lot has changed with the software and hardware since then, let’s take a look at how the new iPad compares to the devices we’re more familiar with.
Native performance
Test
iPad/3.2
iPhone 3GS/3.0
Faster by
100,000 iterations
0.000035 secs.
0.000137 secs.
3.91x
10,000 divisions
0.000010
0.000018
1.8x
10,000 sin(x) calls
0.000012
0.000018
1.5x
10,000 [...]
Here we are on the brink of a new iPhone OS product introduction and developers are facing yet another crunch with device IDs for Ad Hoc testing.
Apple currently lets each iPhone developer, whether a company or an individual account, assign 100 devices for testing purposes. A large chunk of those available devices get used by [...]
I’m too busy right now to write about the iPad in detail, but I do want to make one quick point that I haven’t seen covered in other essays.
An important observation that I’ve made with the iPhone is that it’s perfect for “relaxed” computing. I use it while lying in bed, watching TV, waiting for [...]
As we approach the first anniversary of selling things on the iTunes App Store, I’d like to take the opportunity to look at where we’ve been and where we’d like to go. A lot of good things have happened since last July 11th, but there’s still much room for improvement.
Note: These words may be mine, [...]
What happened?
In spite of plenty of advance warning from Twitter, we got caught by the Twitpocalypse bug.
For the 2.0.1 release, we had tested our software extensively. I actually wrote an emulation layer on top of the code that reads data from Twitter that added a large number to every ID read from Twitter. This testing [...]
The general consensus is that there will be a new iPhone announced next week. I, like others, think it’s going to have new features and capabilities. But how is Apple going to label this new device?
iPhone 3G?
It’s entirely possible that Apple will keep the same name as the previous version. There’s precedence in the Mac [...]
Another area where I find iPhone development to be a bit convoluted was with toolbars and action sheets. The sheets are conceptually tied to the toolbar, yet there is no glue to combine UIActionSheet with UIToolbar. It’s also fairly difficult to represent your application state in the toolbar—an example is the refresh button in Twitterrific [...]
Every once in awhile you read a blog post that completely changes the way you think about a problem. Matt Gallagher’s Cocoa With Love is one of those blogs where it happens often. If you’re not subscribing to his RSS feed, do it now.
In particular, this post addressed a problem that every iPhone developer has [...]