Upgrading to iOS 5 and WiFi Syncing

So I made a start, hopefully for the last time, on the process of rolling up all our devices to the latest and greatest iOS release, iOS 5.

The first thing that's immediately obvious is that the iOS 5 upgrade is significantly slower than most previous updates to the iPad.

It seems that the process that iTunes takes with iOS 5 is as follows:

  1. Back the device up
  2. Completely erase the device
  3. Restore the data and settings from backup
  4. Restore the apps and media from the iTunes library

As you might imagine, this is slow. Really, really slow. The time required to complete this is dominated by the time taken to reinstall the apps. The actual firmware update and restore of the user's data is fairly quick. It's moving the app binaries back onto the device that takes the time. In my experience, it's taking about one hour per device from start to finish.

So, here are some things to look out for:

Firstly, review my article about updating to iOS 4.2 if you don't know the Option-key-to-avoid-downloading-the-update-for-every-device trick. The iOS 5 is pushing 800MB - you only want to download that once.

Secondly, I'd recommend getting a full normal backup of your device before going into the update. When you do update, iTunes will perform a backup regardless - and I have no evidence that this backup is anything less than the full operation - but I'm a bit paranoid.

There's nothing much to report in the process of the update itself. You see the usual on-device progress bars and restarts.

Once the restore starts, you'll see a modal progress dialog then another device restart. Do not unplug the device at this point - none of the apps have been synced back yet. What I'm saying - basically - is don't rush it. Just wait until everything has finally stopped.

Once the restore is fully complete, you can unplug the device. Before you do, though, you might want to turn on iTunes WiFi Syncing in the device's info panel. You have to do this from within iTunes - there's no way to set it up from the device alone. More on this later.

The first time the device is unlocked after the update, you're presented with a shorter version of the on-device setup process. In order, you're asked to:

  • Enable Location Services (or not)
  • Choose a WiFi network (my profiles were still in place so no need to re-enter credentials)
  • Sign in with an Apple ID (I'm skipping this for now)
  • Agree to the ToS
  • Enable automatic sending of diagnostic data (or not)

Once you're through with that, you have an iPad up and running on iOS 5.

WiFi Syncing

My current arrangement for syncing is a computer in every classroom to which the pupils sync their devices over USB. Starting with the youngest kids, I'm moving over to syncing the devices over WiFi (a new feature in iOS 5).

iTunes WiFi sync appears, in iTunes, exactly as if the device were connected to the computer - except it's not connected to the computer. The only visual difference is that the little battery meter beside the device in the source list is not shown for devices connected over WiFi.

The beauty of this is that the classroom teacher can initiate a sync of the entire class set of devices by clicking in iTunes, rather than by having to connect every device to the computer manually. The devices can sit on desks, in schoolbags or in other rooms while they sync.

There's no "sync all devices" command in iTunes but I think you can write an AppleScript that will do that.

For a while, we have been sharing around a couple of 7-port Belkin USB hubs jammed full of iPad cables. While they work, they're neither elegant, convenient nor particularly robust. As of iOS 5, they're now obsolete.

There appears to be no limitation on the number of devices that can be connected to iTunes via WiFi. I have already done more than 10 concurrent syncs to one iMac.

At the moment, my plan is to keep the classroom computer in place and have each class continue to sync to that computer. This allows the classroom teacher some control over what's on the class iPads. In principle, though, I could consolidate all of this onto my (vastly under-taxed) Mac Pro and sync iPads wherever they are in the school.

I haven't yet taken the time to measure the bandwidth load that WiFi syncing creates but I'm confident we will be able to handle it.

The time taken to sync devices over WiFi is not noticeably different to syncing over USB but the fact that you can do so many devices at once means that a teacher could launch their "sync all" AppleScript, walk out the door at 4pm, and the devices would all sync before the morning. No babysitting and cable-swapping required.

Despite the slowness, I already love iOS 5.