UPDATE 3: It is now April 2017 and I have been using my unlocked iPhone 5S for the past year without any problems in Singapore, with a Singapore-network SIM card.
UPDATE 2: In March 2016, I attempted to use a so-net data-only sim in Japan with my iPhone 5S. It did not work, stating that the sim card was not a type compatible with my phone due to it’s settings (unlock settings?) and to contact my carrier about it.
UPDATE: As of 7 January 2016, my phone is finally unlocked! I am using a Singapore prepaid sim card from StarHub which works on the phone.
iPhoneIMEI.net contacted me after finding this post and let me try their service. They will do a factory unlock for your phone using your IMEI code. I was a bit skeptical but was reassured it would work 100%. Their customer service was fast and friendly.
After submitting my IMEI code, it took 3 days (of a possible 1 to 20) before I received an email saying my phone has been unlocked! All I had to do then was plug my phone into iTunes.
I did an iTunes sync but nothing seemed to happen, then updated my phone to the latest iOS. No visible change, so I borrowed a different carrier’s SIM card from a friend to test. Hey – it works on my phone! The incompatibility notice didn’t pop up and the phone got signal and 3G.
I’m so glad this is all over. I can finally use my phone back in Singapore! Still a tad worried until that SG SIM card works but I’m just a paranoid person.
The iPhoneIMEI service for Japan’s au by KDDI costs about £50 (8,500yen/USD72, exchange rates published at time of writing and may differ). You can read other reviews here.
Please note that the Shutter Sound will still remain on your phone. I haven’t found a way to make it disappear.
*** Previously written post below ***
Here is the simple answer: YOU CAN’T. Well, not legally anyway. (Yet?*)
Edit 2: I asked around about the R-sim. It supposedly only works overseas with an overseas sim card, and you will need one on hand to activate it. A friend told me he tried it and the reception etc was horrible, others seem to recommend it. Go to the electronic town in your area (Akihabara, Den Den Town etc) or get it off Amazon. Never tried personally so I don’t know.
Edit: I’ve found a few online unlock sites that will do a factory reset for you but it will set you back up to $250. One site I asked is unable to unlock au phones as they use CDMA technology which can rarely be unlocked.
au won’t do it. The Apple store won’t do it. No matter how many times you ask au, or even if you’ve cancelled/ended your contract and paid for the phone in full THEY WON’T DO IT.
The Japanese Apple store staff took 20 minutes to explain to me that only sim-free phones sold at their store could work with foreign sim cards. He stated that “foreign sim cards might destroy your phone” or cause it to function weirdly, not be compatible bla bla bla then said I should just buy a new sim-free phone from them. EXCUSE YOU, I AM NOT MADE OF MONEY.
One non-Japanese staff at au told me point blank to go find some store to illegally unlock it. “Other Taiwanese and Chinese customers did that”, she said, “but well, you’d have to find a reputable store”.
“Your phone can now only be used as an iPod touch”, the staff chirped joyously, oblivious to my anguish, when I asked on another visit. “You know, it’s just as good as long as you have wifi!” EXCEPT IT IS USELESS AS A PHONE THANK YOU VERY MUCH. And it’s not like I radiate a wifi hotspot naturally y’know?
I pleaded with them. Told them I was leaving Japan (帰国する kikoku suru), reasoned that since I’d be cancelling my contract (解約 kaiyaku) hey, I paid for and now own this phone I WILL PAY YOU TO UNLOCK IT. It is a waste (mottainai) to get a brand new phone because my iPhone still works perfectly fine (2 min after I wrote this I dropped my phone and it ricocheted off the side of the wall and hit the floor BUT IT IS STILL OK) also I AM NOT MADE OF MONEY and phones do not fall from the sky.
Based on this Japan Times article, carriers are supposed to get rid of the SIM lock*, but it seems they won’t do so for iPhones or only sell certain handset models SIM free. Which is just as useless as ever.
I should have probably jumped to another carrier when my first contract with au ended but I liked au and preferred to stay naively, only to have them end my student fee wavers (it only applies for a maximum of 3 years supposedly) and give me endless headaches with this SIM lock issue. But I suppose any other carrier would have said the same thing.
I’ve also just paid over $600 in total for cancellation fees and the rest of the payments for my iPhone. This beats paying almost 10,000yen ($100) a month for a phone that DOES NOT WORK AT ALL OVERSEAS since I’ll mostly be out of Japan before the period my contract ends. If I want to use my phone (aka actually get any RECEPTION) it will cost me 2,000yen ($20) a day. How about No.
They do not accept payment via credit card. It’s cash only or a direct bank withdrawal (if you had been paying your bills that way) but hey I had $0 in my bank after all the shipping and moving out fees. So I had to switch my payment method to credit card which takes like, a week or some other really long time to take effect.
Also, just a heads up when you cancel your contract it happens immediately. You can’t cancel in advance (since you’re still paying for any usage in that month anyway) or have it cancel at the end of the month.
I was leaving Japan on 1 July, and thought they could automatically cancel it on the 30th but noooooooooo it doesn’t work that way. I ended up rushing over at 8pm on the 30th for them to cancel my phone contract and it immediately stopped working. You know, mobile data would have been a great solution for all the trouble I had at the airport the next day…..
Online “unlock your iPhone bla bla bla” places didn’t seem to be able to provide their service for a Japanese carrier locked one. Bleh. Some forums advice to jailbreak your phone. Nuh uh that doesn’t work.
Shops I’ve asked here in Singapore won’t do it, say they can’t do, it so now my 1.5 year old iPhone 5S has now become an iPod touch. Great.
So, keep this in mind before you sign that contract with a Japanese carrier. Buying a contract-free, SIM-free iPhone from the Apple Store will be a better choice that will save you much, much, trouble later on.
*note: Based on this post on Japan Mobile Tech, KDDI and Docomo phones WILL be unlocked, under certain conditions, but this is only applicable for phones that go on sale after May 2015. Thus meaning it does not apply yet to the iPhones which were already released before the new law came into effect.