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iOS User Accounts

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Wouldn’t it be convenient if you could pick up any iPhone or iPad and have it personalized with your settings quickly? This is something that occurred to me last week when my girl friend had left her iPhone at home and wanted to continue reading her book in iBooks. I had my iPad with me but of course it is tied to my iTunes account, not hers, and it’s way too much hassle to reconfigure it just for a brief reading session.

But it made me wonder what such a feature could look like on iOS and what it would take to make it happen. Basically, you’d want an extension of something that’s already possible on OSX: signing in with an Apple-ID. Once you’re authenticated with your Apple-ID, your content and settings are only a few steps away: iCloud, if you’re using it, has got it and in theory, that’s all you need to restore your device.

I’ve upgraded quite a few devices in the past and so far backup and restore has worked really well. Now imagine there were an (optional) login screen on iOS devices where you could log in to your iCloud account and immediately you’d get your home screen, with your content and settings trickling in in the background – just like it’s happening now when you restore through iTunes or from iCloud. With future devices having more storage space, the OS could cache multiple user accounts so that on subsequent logins your data would only need an update rather than a completely fresh pull. Also, you can imagine some things like big apps being referenced from multiple accounts and therefore needing to be stored only once on a device and not per account.

If that use-case still sounds esoteric to you, because your iPad is yours alone, think about places where iPads could be shared by larger audiences: Schools, universities, sales people, etc. For example, if a school wanted to start using iPads in one course only, say their biology class, they’d only need to get enough iPads for their maximum class size, not for the total number of students attending that class. (Caveat: no iPad based learning at home unless students log in using their private iPad.) Or there could be iPads per course that wouldn’t need to be moved: Your course material appears at your desk wherever you are – you don’t actually carry it there anymore. It would certainly help reduce the risk of iPads being dropped between classes or on the bus.

Technically, I would assume something like that being investigated or even in place already at Apple. It’s probably just a matter of broadband connections catching up to make this a smooth experience. One that Apple would be willing to ship and tout as a new feature.


Written by sas

February 7, 2012 at 19:02

Posted in apple, iphone

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Using S/MIME on iOS Devices

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The following article explains how to set up your iPhone or iPad to send and receive encrypted emails via S/MIME. Prerequisite is an S/MIME certificate from a certificate authority. Some CAs provide them free for personal use. The procedure is not very complicated even though the description may look lengthy due to the many screenshots. The biggest hurdle is to pick the correct file format when exporting your S/MIME key on your Mac. (A description on how to export the correct certificate on Windows will follow.)

Set-up for Receiving Encrypted Emails

1. Export your private key in a format that you can import on your iOS devices.

To do this, open “Keychain Access” and find your certificate. Select it and choose “File” / “Export Items”, as shown below.

01 export key


2. Next, save the certificate in p12 format.

In the process of saving the certificate, as detailed below, you will be asked to provide a password to encrypt your key. This will allow you to send it via email without fear of it being intercepted and used by someone else. Depending on your keychain settings you will also be asked to provide your administrator password to read the privatekey for exporting.

02 save p12

3. Now drag this exported file to your icon to send it to yourself.

(Make sure you don’t encrypt it 😉

03 send key

4. Turn to your iOS device to import the certificate.

Open the email you just sent to yourself and tap on the attachment to import your certificate.

04 import on ios 05 unsigned certificate 06 enter password

5. Enable S/MIME in advanced mail settings and choose your certificate.

On your iOS device go to “Settings” / “Mail, Contacts, Calendars” / “<Your Account>” / “Advanced” (at the very bottom of your account settings) and activate S/MIME. Important: Make sure you leave the account settings by tapping “done” in the top right of the tool bar. Changes don’t appear to be applied until you do so.

07 enable smime 07b confirm settings

You can also enable signing and encrypting of messages here but more on that in a moment. What we’ve achieved so far is being able to read messages that have been signed with our public key. Unfortunately, sending encrypted messages involves a few more steps and has a few caveats.

Set-up for Sending Encrypted Emails

In order to send an encrypted message, you need to do the following.

1. Import the recipient’s public key.

This happens automatically in on OSX but requires some manual interaction on iOS. You may have noticed when looking at signed messages (like the one you sent yourself earlier) that there’s a new little star icon in the blue email address bubble after S/MIME has been activated. This is the UI indicator for signed messages. And the address bubble is also a button that you can tap to bring up address – and certificate – information.

08 address bubble star

Tapping this button will bring up the address info view:

09 address info

Tap install to register this public key, which will allow you to send encrypted emails to the key’s owner. You will need to repeat this procedure once for every recipient.

2. Send email.

There’s not really a step two other than making sure you’re sending to the recipient’s correct email address and from your correct account so that the available keys match up with the email addresses used in the process. You can tell that your message is being encrypted by the “Encrypted” string in the title bar of your message:

10 encrypted message


What’s a bit unfortunate is that there’s no easy way to selectively send encrypted emails. The encryption setting is global for the account under “Settings”, meaning that you have to go there and enable/disable encryption for all messages from that account. It would be nice if that were the default only, with an option to override it in the message composition view.

It would also be nice if public key importing were automatic, like it is on the Mac.

But all in all, it’s nice to be able to read encrypted emails on iOS devices now.

Written by sas

December 12, 2011 at 09:12

EasyPay in the Apple Store 2.0 app

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In the latest 5by5 Talk Show John Gruber and Dan Benjamin speculate how EasyPay in the Apple Store 2.0 app works. EasyPay is a feature that allows shoppers to scan an item’s barcode and complete a purchase via their iTunes account without any interaction with the shop’s staff.

John and Dan are puzzled by how Apple prevents someone from just walking out without properly scanning and purchasing an item.

My wild guess would be the following happens: The barcode contains an RFID chip that will allow sensors at the exit to tell when an item is removed from the store. The barcode also contains an ID that is associated to this RFID in the store’s inventory system. When you scan the barcode and purchase an item, the RFID associated with that item is cleared to leave the store and will therefore not raise an alarm.

Maybe that’s one reason this only works in US stores right now.

Written by sas

November 10, 2011 at 13:11

Posted in apple

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Apple Digital Media Library?

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Please don’t call it cloud…

I’m setting up new macs quite regularly and I’ve found over the years it’s gotten easier to switch from one work Mac to another. There was a time when I had a strict “main work machine”, a macbook, which would have all my latest data and apps I use with a fallback machine for testing, heavy duty compiling, etc. This was typically a desktop.

The idea was to be able to work everywhere using the laptop and switch to the desktop if required for stuff the laptop couldn’t handle well. Thanks to faster internet connections and better synchronization options I find that nowadays I regularly swap machines depending on wether I want the bigger screen of the desktop or the better mobility of the laptop. I have my source code in a subversion repository off-site, my contacts and calendars sync via and my mail is hosted on an IMAP server. That covers pretty much everything I need for work. Except maybe for open source software, which I install on one machine and rsync to the other.

When I looked at this process I thought I might as well sync my iTunes and iPhoto Libraries with rsync to benefit from the bigger desktop screen and the speakers. And then I thought – why do I have to do this when my contacts, my calendars and my mail are available on all my macs pretty much out of the box? Isn’t it odd that we buy not only music but movies, tv shows, and now apps from the iTunes Music Store? When will Apple rename this to the Apple Digital Media Store and consolidate our iTunes Music and iPhoto Library into a Digital Media Library, offering local network (maybe even remote network) synching?

Written by sas

November 7, 2008 at 14:11

Posted in apple