Area Mail Works on the Nexus 6 purchased from the Google Play store

I currently own a Nexus 6 that I purchased from the Google Play Store about a month a ago. One of the features of Android 5.0+ is that when you insert a carrier SIM card it will install carrier specific apps to your phone. I was pleasantly surprised that it installed the NTT Docomo Area Mail app for emergency alerts. I was quickly disappointed when it said that it didn't support my phone so I uninstalled the app.

With the strong earthquake that we had today I was surprised that I got an Area Mail alert even with the application not installed.  I did find that the "Cell Broadcast Alert Service" was running and had started at the exact time the earthquake started.

Comparison of a Samsung Galaxy S6 unlocked by Japan's big three carriers

As expected, Softbank Mobile announced that it will also adhere to the new guidelines and begin unlocking phones brought new to market from this month. This includes the Samsung Galaxy S6 Edge. The terms are exactly like Docomo's: unlockable from 180 days after purchase until 90 days after the phone is disconnected. Unlocking within that 90-day window for an out-of-contract product will also require a trip to certain softbank stores and therefore cost ¥3,000 plus tax.

Unlocking terms by carrier

	KDDI	docomo	Softbank
Cost	Free (¥3,000+tax in store)	Free (¥3,000+tax in store)	Free (¥3,000+tax in store)
Applicable to devices released from	April 23, 2015	May 1, 2015	May 29, 2015
Wait time to unlock	180 days	6 months	180 days
Unlock possible after cancel service	forever	for 3 months	for 90 days

Galaxy S6 Edge Comparison

Right now, the only phone that will be unlocked by all three is the S6 Edge.

	KDDI	docomo	Softbank
Cost with MNP (without)	¥33,480 (¥55,080)	¥29,808 (¥58,968)	¥21,600 (¥53,760)
Earliest unlocking date:	October 20, 2015*	Now	November 25, 2015
Unlock cost	free	¥,3000	free
LTE Bands:	1, 3, 18, 26, 28	1, 9, 19, 21, "700"*	1, 3, 5
WCDMA (3G) Bands:	1	1, 5 (or 6?), ?	1, 5, 8

* The exact bands are ambiguous. docomo simply lists "700" which could be one of 12, 13, 14, or 17 or perhaps all may be covered because the frequencies are either adjacent or overlapping. Also, both KDDI and docomo list support for "800". KDDI specifically states this is band 18. I believe that docomo uses band 19. The uplink frequencies are overlapping and the downlinks are close but not adjacent.

Figuring out which bands are supported

KDDI is the only carrier clearly indicating this an in easy to understand way. Their bands are published here. Softbank's are on the product's specs page (SBM S6 Edge). Docomo's are also listed on the spec page, but only for LTE (DCM S6 Edge). To get the 3G bands is a real pain, but docomo will be required to make this more transparent once they release phones under the new guidelines.

Docomo classifies the S6 Edge as a "class 5 world wing" device, which looking up here gives contradictory information. The product pages lists LTE bands "2GHz, 1.7GHz, 1.5GHz, 800MHz, and 700MHz". However a class 5 world wing device supposedly supports LTE Band 1 (2.1GHz), Band 3 (1.8GHz) and "others" such as Bands 4, 17, 20 "etc" as well as "3G" (whatever the hell that means) and "3G850".

LTE（Band 1（2.1GHz）、Band 3（1.8GHz）、その他（Band 4、Band 17、Band 20など））および3G、3G850、GSMネットワークをご利用になれます。

I'm just guessing here, but since the most common 3G band (except in North America) is Band 1 (2100 MHz), I am guessing that "3G" refers to Band 1 and that 3G850 refers to Band 5 (Actually I'm told that what docomo calls "3G850" is actually Band 6). I also assume that it doesn't support AT&T's Band 2 (1900 MHz, aka PHS) or T-Mobile's Band 4 (1700/2100 MHz, aka AWS).

Digging ever deeper into docomo's i–mode-like labyrinth of a website confirms no support for 3G in North America.

KDDI SIM unlocking conditions are better than docomo's

Both KDDI (PR) and docomo (PR) have announced their respective unlocking conditions in compliance with the new Somusho guidelines. At this point in time, there appears to be some major differences in the KDDI and docomo conditions. Media inquires indicate that docomo will only unlock phones for the original owner, where as KDDI has responded that it will unlock any phone, irrespective of the current owner. (This of course won't apply to stolen phones). Additionally, the rumor is that docomo will only unlock phones for three months following termination of service, even for the original owner.

However, keep in mind the following two points:

1. Neither company is actually unlocking phones under the new guidelines yet.
2. Such glaring differences in service conditions have a way of leveling out. (Remember the debacle that was Softbank's tethering and 1.2 GB data cap)

So by the time six months have passed from the release of the docomo summer lineup, it is entirely possible that docomo will match KDDI's conditions (though on the other hand this is docomo who is used to being the ones to dictate conditions to the other carriers – so we'll just have to see). There were (are) no similar restrictions on the unlocking period for docomo phones to which the old guidelines apply.

	KDDI	docomo
Cost	Free (¥3,000+tax in store)	Free (¥3,000+tax in store)
Applicable to devices released from	April 23, 2015*	May 1, 2015
Wait time to unlock	180 days	6 months
Unlock possible after cancel service	forever	for 3 months

* The "Galaxy S6 edge SCV31" on sale from April 23 from KDDI is subject to the new guidelines and will be unlockable 180 days from purchase. (This phone is also currently unlockable now from docomo but for ¥3,000.)

So is this a good or bad thing? It depends on how you look at it.

Previously, docomo was the only option for obtaining an officially-unlockable phone, and that cost money and time, lots of time if you ended up with incompetent shop staff. It was also difficult to figure out which bands a docomo phone supported. And most incredulously, unlocking your phone pretty much voided the warranty. All that crap will be finished, but there could now be a finite time window during which a docomo phone can be unlocked.

KDDI frequency bands

KDDI has already published a page showing WCDMA and LTE band support of its unlockable phones. Also, I can't help but roll my eyes at the "SAMSUNG" prefacing "Galaxy S6 Edge" ;)

As can be seen here the "Samsung" Galaxy SG Edge will work fine in most of the world except North America, where it lacks support for "GSM" carriers AT&T and T-Mobile. Maybe it'll work on EDGE, but the experience will be horrible.

What about Softbank?

As usual, there is no word at all from Softbank, and the only phones they list as unlockable are the same shitty ones that no one ever bought. They blatantly ignored the old guidelines for quite some a long time. I assume they'll comply this time but not sure when.