Update (as of 13 March 2015): these instructions still work for iOS 8.2. Happy downloading!
There are tons of fantastic free apps on the Japanese App Store that don’t show up when you search from an overseas iTunes account. From navigation tools to puzzle and card games, Japanese iTunes account holders are spoilt for choice. However, there is an easy way to get around that virtual barrier — all you need is an existing iTunes account and a bit of Google-fu.
First, flick over to your iPhone or iPad’s Settings, scroll down to the iTunes and App Store tab, and tap on it. Tap on the Apple ID tab, and an Apple ID pop up will appear. Tap on the View Apple ID tab to jump to the Account screen.
On the Account screen, tap on the Country/Region tab — it should take you to the Change Country/Region screen. Tap on the Change Country/Region as well. In the next screen, tap on the Store tab and a roll tab will appear. Scroll to the very bottom, and Japan (日本) should show up. Select that option.
When Japan has been set as the Country or Region, tap on Next. It will take you to the iTunes Store TOS — tap on Agree for the pop up to appear. Tap on Agree again and you will be taken to the Billing Information page.
Tap on None for your payment settings if you only intend to download free apps, otherwise input a Credit Card number (note that the system will only accept credit cards issued in Japan). Input your name, Japanese address, and Japanese telephone number (for the latter two, put your Google-fu to good use). Hit Next and you’re done!
You can check your Account settings screen again to confirm if your country has been set to Japan (the Japanese flag should be displayed). Enjoy your new Japanese iTunes account! You are now free to download as many apps as you like that were previously only available to Japanese iTunes users :3
Additional Note
You can switch back to your original country’s store without having the Japanese game or app disappear from your device. You will, however, need to switch back to the Japanese store when the Japanese app requires an update.
JPOP Manila 
Can I switch back to my country’s store once I download a Japanese game or does the game disappear?
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Yes, you can switch back to your original country’s store without having the Japanese game or app disappear. You will, however, need to switch back to the Japanese store when the Japanese app requires an update.
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For me, There’s no option for ‘none’ on the payment methods. Is there anyway around this? Thanks!
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Hmm that’s strange — I just checked on my phone and I still have the “None” option. Can you try starting over from Step One and make sure you get everything right?
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i dont have the none option.. i only have visa, amex, mastercard, jcb and diners club, and ive tried multiple times 😦
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Hi — I just checked my phone, and I still get the None option on the menu. Please try again, and carefully follow the steps — you may be missing a step or two.
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um.. can i do this method on my mac book? or does this method only works on iPhones and iPads?
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Apparently it works on iTunes also — but please check it yourself as I rarely use iTunes on a computer.
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I did this on the new itunes12, it has a none option, i did it from my computer
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Good to know — I rarely use iTunes on my laptop so I haven’t checked.
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how? that option didnt appear on my laptop.
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hey, can you please change my account settings on your phone yourself? I have tried so many times before, but the none option just didn’t appear please?
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Sorry but I prefer not to access the accounts of strangers even if they gave permission. Please follow the instructions on the site instead. They still work — I just checked. Thanks.
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Hi can you please look into why there is no none opyion as I have been trying for a month now on my iPad and if not can you please go in my account and change thank you
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Sorry but I prefer not to access the accounts of strangers even if they gave permission. Please follow the instructions on the site instead. They still work — I just checked. Thanks.
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How do I do the Japanese Address part? Thanks!
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It’s already in the post: use Google to find one.
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I’m looking for the game dragon ball tap battle but it still isn’t there
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I think the “none” option doesn’t show up if you’ve ever had a credit card associated with your iTunes account.
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I atill couldn’t download any of the apps in the Japanese apps store
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