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Thunderbird · Apr 29, 2010, 11:25 AM

I guess this is speculation, since nobody has a 3G iPad yet to confirm, but...

The news page of MacNN today shows the new AT&T Micro SIM. Since it is simply a cut out inside a full size SIM, could a user:

Call up AT&T and switch their iPhone plan to that new SIM...
Punch out the micro SIM, but save the extra plastic piece as an adapter for the iPhone...
Then use the same SIM interchangably between iPhone and iPad on the iPhone data plan?

turtle777 · Apr 29, 2010, 11:36 AM

Good question.

Once the iPhone HD goes on sale, it will include a Micro SIM.

Could that be interchanged ?

-t

Big Mac · Apr 29, 2010, 11:36 AM

If you switch the iPhone plan to that sim, would good would it be to use it? How would it help?

Thunderbird · Apr 29, 2010, 11:46 AM

Originally Posted by Big Mac

If you switch the iPhone plan to that sim, would good would it be to use it? How would it help?

Because you wouldn't have to pay for a separate data plan for the iPad. You could just take the SIM card out of your iPhone and put it in the iPad when you needed 3G. For somebody that might only occasionally need 3G on the iPad, this could potentially save quite of bit of cash.

Simon · Apr 29, 2010, 12:59 PM

Once you've punched the micro SIM out I doubt you'll be able to get it into the iPhone together with the rest of the regular SIM.

Of course if OTOH the iPhone HD switches to micro SIM that might turn out to work quite nicely for future iPhone HD owners.

-Q- · Apr 29, 2010, 02:57 PM

Knowing AT&T, they'd probably block an iPad from using a SIM card associated with an iPhone device ID.

jokell82 · Apr 29, 2010, 03:05 PM

Originally Posted by Simon

Once you've punched the micro SIM out I doubt you'll be able to get it into the iPhone together with the rest of the regular SIM.

Of course if OTOH the iPhone HD switches to micro SIM that might turn out to work quite nicely for future iPhone HD owners.

And there may be micro SIM to SIM adapters.

Eriamjh · Apr 30, 2010, 09:57 PM

My guess is the iPad SIMM won't allow you to make calls.

CIA · May 3, 2010, 03:27 PM

Not being able to make calls.... True, but...

If I have a old iPhone that I've replaced with a newer one and wanted just data on the old one. I could slap my data only iPad sim into the old iPhone (via micro sim adaptor) and just have data access for web, email (Skype?) etc... Could be useful for trips where I didn't want to lug around a full iPad.

tooki · May 4, 2010, 06:18 PM

Seems to me that it’d be pretty trivial for a third party to make replacement iPhone SIM card trays to hold micro SIMs.

Simon · May 6, 2010, 03:18 AM

The problem is not so much cutting the plastic card, but that in some cases people will also have to cut parts of the contacts. You have to take care not to destroy the SIM's chip itself there.

This image shows the above SIM but 'trimmed' to mimic a micro-SIM (note the clipped contacts). It's inserted in an actual iPad 3G micro-SIM card carrier:

turtle777 · May 6, 2010, 03:22 AM

Originally Posted by Simon

From this pic, it looks impossible to create a micro SIM from a regular SIM w/o cutting into the contacts.

Look at the upper edge of the micro SIM. The contacts start about 0.5mm from the edge.

-t

Simon · May 6, 2010, 03:29 AM

That's precisely my point.

In the lower picture you can see that same red SIM card after trimming in the iPad's micro-SIM carrier. And according to the reports it worked just fine.

"As we were tempted to find a way to make this 3G model fully working on a french carrier network, we decided to cut the SIM car (here from SFR carrier), originally defined for a 3G USB key.
...
We will not provide details on how to cut the SIM card to turn it into a micro SIM; as the procedure is really tricky, and you have more chance to destroy the chips than to have it working at the end (you need to destroy/cut out some contacts)"

The point is you can do this. But you're probably going to have to be rather careful.

turtle777 · May 6, 2010, 06:56 AM

Originally Posted by Simon

The point is you can do this. But you're probably going to have to be rather careful.

And it's only possible with the carrier.

If the micro SIM was inserted directly, there was no way it would work.

-t

Simon · May 6, 2010, 07:21 AM

Originally Posted by turtle777

And it's only possible with the carrier.

If the micro SIM was inserted directly, there was no way it would work.

Indeed. Note the two strips of tape they used.

-Q- · May 6, 2010, 11:04 AM

Originally Posted by turtle777

From this pic, it looks impossible to create a micro SIM from a regular SIM w/o cutting into the contacts.

Look at the upper edge of the micro SIM. The contacts start about 0.5mm from the edge.

-t

Apparently, it's not that impossible:

How To Convert a SIM to a MicroSIM with a Meat Cleaver!

The Godfather · 09:52 PM

The staff at commfreaks did the opposite: adapt the microsim for use in the iphone.
No sir, you can’t use the iPad’s SIM in the iPhone

- Commfreaks.com
Commfreaks.com - Creativity in Embedded Linux, Communications and Controls

Their results are more surprising, as they found that the iPad's microsim is detected by the iPhone, with five bars and 3g, but the iphone would NOT be able to use the internet.

The Godfather · May 14, 2010, 07:15 PM

That blog is full of BS. These people made it work.
Using a Micro SIM in an iPhone 3G - Hijinks Inc.

WillyBreaker · Jun 21, 2010, 03:00 PM

I used special template and this video guide YouTube - How to make MicroSIM - TEMPLATE INCLUDED! to cut my SIM. It took just 2 minutes, everybody can do it, and templates will not let you cut contacts accidentially.

Eriamjh · Jun 22, 2010, 12:14 PM

I need people to try their iPhone4 sim in their iPad and tell me if 3G works.

schalliol · 12:40 PM

Originally Posted by Eriamjh

I need people to try their iPhone4 sim in their iPad and tell me if 3G works.

IT WORKS IT WORKS!!

You see the items in my sig, I pulled out my iPhone 4 SIM and put it in the iPad 3G and it works perfectly for 3G data (shows full signal and 3G right now). I did not click on the "Cellular Data" View Account button. The iPad 3G had an unlimited connection on the iPad 3G SIM prior (disclosure in case this works because the iPad knows it has 3G for right now). If you're curious and haven't heard, the SIM trays are different sizes. The iPhone 4 SIM tray is actually bigger than the iPad's and has a notch in it.

jokell82 · Jul 5, 2010, 11:08 AM

Originally Posted by schalliol

IT WORKS IT WORKS!!

You see the items in my sig, I pulled out my iPhone 4 SIM and put it in the iPad 3G and it works perfectly for 3G data (shows full signal and 3G right now). I did not click on the "Cellular Data" View Account button. The iPad 3G had an unlimited connection on the iPad 3G SIM prior (disclosure in case this works because the iPad knows it has 3G for right now). If you're curious and haven't heard, the SIM trays are different sizes. The iPhone 4 SIM tray is actually bigger than the iPad's and has a notch in it.

Did not work for me. Had a 32gig 3G iPad that was NOT activated on AT&T, and put my iPhone 4 sim into it. It still said that it had no account and couldn't connect.

schalliol · Jul 6, 2010, 06:42 PM

Very interesting. It sounds like once AT&T tells the software it's ok, the iPad allows connections, but once it checks and finds that there's no account, it doesn't work. Thanks for the report.

Wiskedjak · Jul 6, 2010, 08:40 PM

Originally Posted by jokell82

Did not work for me. Had a 32gig 3G iPad that was NOT activated on AT&T, and put my iPhone 4 sim into it. It still said that it had no account and couldn't connect.

You might need to change the APN settings on the iPad. I believe AT&T has a different APN between their regular cell service and their iPad plans. Find out what your iPhone's APN is and enter that into your iPad.
AT&T iPhone's APN settings?