iOS4 on iPhone 3GS

[nodric]

Applications that support multitasking in iPhone OS 4 and later should do the following:

• (Optional) If you want to do actual work while in the background, you need to request permission to continue running. For more information about the types of work you can perform, and how to request permission to do that work, see “Executing Code in the Background.”

Firstly, an excellent reply! Your explanations were clear and concise.

I guess the statement above is my only concern. I run enterprise projects, and don’t code anymore, so cannot profess to have the deep understanding of app dev on iOS, and therefore don’t know all the functions that apps will be allowed to persist whilst in the background.

The Optional bit sort of says, that a well written app will warn you as it drops out of view, that it’s going to eat some power while it’s away, but a badly written app won’t…

My 2nd gripe, and it’s probably only me that cares, having all the apps default to the task switcher, just ends up giving you a huge long bar to scroll through. Just not very clutter free or organised. They give us folders (so overdue), then plonk 50 icons we don’t need on a task bar. Much better would be to only locate multi-tasking aware apps there, and have a way to select which can multi-task, in the same way we can manage notifications, or location awareness.

Maybe I’m being too picky, but imagine if all apps could use notifications, or know your location, without you being able to control them!

[rhubarb]

I've found a couple of problems since upgrading my 3gs.
I was fiddling with it the other day, don't recall exactly what I was doing, but it suddenly went into text messages for no reason. Opened up on a message I'd received from someone on 6th June.

Just now I've deleted a couple of photos, and its replaced them in the camera roll with black boxes.

Nothing huge I know, but a bit annoying.

Rhubarb.

[NickFitz]

Here's an excellent explanation of what fast app switching is and isn't.

[NickFitz]

After a few days playing, John Gruber of Daring Fireball weighs in with a review.

Key points (including at least one typo at his end):

• "As I wrote after examining Apple’s iPhone 4 demo units after the WWDC keynote, the Retina Display’s overall effect is like that of high-end glossy magazine print — except that it updates live. It’s living breathing print. I don’t recall ever having seen motion graphics of this resolution, anywhere."
  
  
• "The overall build quality seems impossibly good. The iPhone 4 is beautiful to behold and feels like a valuable artifact. It’s like a love letter to Dieter Rams."
  
  
• "The big win for Apple’s A4 system-on-a-chip, I suspect, is not raw performance (even though it is faster), but rather performance-per-watt. It’s an even better balance between speed and power consumption. And, on a related point, the A4 system is physically smaller, which has enabled Apple to reduce the size of the iPhone form factor and still include a bigger battery."
  
  
• "...for obvious reasons, the glass back raises concerns about the iPhone 4’s droppability. With previous iPhones, it was liking dropping a piece of buttered toast — there was a lucky and unlucky side on which it could land. With the iPhone 4, it’s like dropping a piece of toast that’s been buttered on both sides."
  
  
• [FaceTime]: "The video quality is far smoother than anything I’ve ever gotten using Skype or over AIM with iChat — better resolution, far fewer compression artifacts, and almost no pauses or lag. It’s early in the game, but so far FaceTime seems best-of-breed technically... Audio quality over FaceTime is excellent. This is particularly noticeable with calls that start using voice. The difference is so stark that it makes me wish FaceTime could kick in for audio-only calls between FaceTime-capable phones. AT&T should be ashamed... It’s also the sort of thing that drives critics of Apple products nuts. “Look at these stupid people who think Apple invented video chat, or even mobile video chat.” Right? What they’re overlooking, and will always overlook, is the value of the “It just works” factor. Normal people aren’t just going to use FaceTime — they’re going to love it."
  
  
• "Mark these words: FaceTime goes down as one of the most important things Apple has ever introduced."
  
  
• "It’s a subtle change, but Apple has changed the system font for the iPhone 4, from Helvetica to Helvetica Neue... There is, however, one problem with Helvetica Neue in iOS 4.0: it doesn’t include italics. You can see this for yourself on this web page I’ve created that specifies Helvetica and Helvetica Neue alongside each other, including spans of bold, italic, and bold italics." Note to John Gruber: crappy link text there; it could be linking to anything. How about "this demonstration of Helvetica and Helvetica Neue alongside each other" and adjust the rest of the paragraph accordingly?
  
  
• "I thought last year’s 3GS provided a nice improvement to the iPhone camera, with superior still photos and the addition of video. The new (primary) camera in the iPhone 4 is a bigger improvement. Still photos are of the quality of a low-end dedicated point-and-shoot camera, and the 720p video is surprisingly good."
  
  
• "There are two widely-reported problems with the iPhone 4."
  
  
  • "First is the issue surrounding 3G reception and hand placement on the device... I haven’t been able to duplicate the problem on mine, though. Sometimes, but rarely, I can make it drop a single bar, but I can’t duplicate the drop to “No Signal” that many others can... It definitely seems related to signal coverage (or cell tower proximity, or something like that). I’ve received many emails (and a few tweets) from DF readers who can reproduce the problem at will in one location, but can’t in another."
    
    
  • "The other issue regards the proximity sensor — the sensor which turns off the touchscreen when you hold the phone to your head for a call. The proximity sensor on the iPhone 4 seems far more sensitive than on previous iPhones, such that minor movements away from your head during a call re-enable the touchscreen, which then leads to your cheek inadvertently engaging the Mute or End Call buttons... This problem, I have seen myself. My cheek invoked the End Call button during a call yesterday, something that I don’t recall ever having happened in the three years I’ve been using iPhones."
  
  
• [Apropos the signal loss issue]: "It may wind up being more of a publicity problem than a technical one. At the very least it isn’t going to help the iPhone’s perception as a great device but weak phone."

Make of that summary what you will, but it's well worth reading his whole review (relinked to save you having to scroll back up, despite the fact that I thereby contradict my criticism of his link above - wotever, Google's smart, it'll work out that the first link is the meaningful one ).