1. BBHermes's Avatar
    Greetings,

    I would like to purchase an unlocked Z10 that works with T-Mobile WiFi calling in the US. What STL model or specs do I need to verify for this?

    Also: I'm looking at ebay; are there other reliable sources I can search for good prices? I did order one through the BB store a few days ago when they had a sale, but that was limited to one-per-person and who knows when something like that will be offered again...

    Thanks!
    12-06-13 12:38 PM
  2. raino's Avatar
    STL100-3 is the variant you want to get; if you can get the RFK121LW sub-variant, even better.

    You likely won't find new Z10s at/around $200 anywhere.
    12-06-13 12:53 PM
  3. BBHermes's Avatar
    if you can get the RFK121LW sub-variant, even better.
    Thanks, much appreciated. How can I verify the RFK121LW sub-variant? First time I've heard of a "sub-variant"; I learned something new today!
    12-06-13 12:57 PM
  4. raino's Avatar
    Thanks, much appreciated. How can I verify the RFK121LW sub-variant? First time I've heard of a "sub-vaariant"; I learned something new today!
    If it's a T-Mobile branded Z10, it's RFK121LW. If it's AT&T branded, it's RFF91LW. If it's factory unlocked, it could be RFF91LW too.

    On paper, The RFK121LW is supposed to have all of TMO's radio bands. But from what a lot of people have posted here, the sub-variant doesn't really seem to matter; both work just as well on TMO.
    12-06-13 01:00 PM
  5. BBHermes's Avatar
    Ok, thnx... When my unlocked z10 from the BB store arrives, how can I check? Will it be stamped on the box or the phone, and where exactly?

    If both sub-variants work the question is moot as you point out... but I'm curious to know, nonetheless.
    12-06-13 01:15 PM
  6. Jim Wolfson's Avatar
    Ok, thnx... When my unlocked z10 from the BB store arrives, how can I check? Will it be stamped on the box or the phone, and where exactly?
    Checking my T-Mobile's Z10 box, the subvariant isn't printed on the label; for the 121LW variant, it should list the following frequencies:

    GSM: 850/900/1800/1900 MHz
    UMTS Band I (2100), II(1900), IV(1700/2100), V(850)

    Note that you'll have to use T-Mobile's OS releases if you want WiFi Calling; it doesn't work with the leaks, at least so far.
    12-06-13 01:18 PM
  7. BBHermes's Avatar
    Note that you'll have to use T-Mobile's OS releases if you want WiFi Calling; it doesn't work with the leaks, at least so far.
    Ok thanks... This make me wonder though: When T-Mobile-US finally releases an official 10.2.x in the US, I wonder if a gsm unlocked Z30 would then be able to do wifi calling... Based on your comment, maybe it's the OS holding things back on the z30, not the hardware as I originally thought...
    Last edited by ishamid; 12-06-13 at 02:24 PM.
    12-06-13 01:50 PM
  8. raino's Avatar
    Ok thanks... This make me wonder though: When T-Mobile-US finally releases an official 10.2.x in the US, I wonder if a gsm unlocked GSM Z30 would then be able to do wifi calling... Based on your comment, maybe it's the OS holding things back on the z30, not the hardware as I originally thought...
    I would say the hurdle is definitely on the OS end rather than the hardware end, especially since WiFi calling on BB10 devices is no longer UMA.
    12-06-13 02:05 PM
  9. Jim Wolfson's Avatar
    I believe T-Mobile supports WiFi Calling on all subscriber phones that are hardware capable of doing so, but if they don't sell the Z30 (I don't know if they do or not) the WiFi Calling app may or may not work. I'm sure there are T-Mo subscribers with a Z30 who could answer that question.

    It's not the OS per se "holding things back", but T-Mo hasn't released an updated WiFi Calling app that works with 10.2.xxx releases - at least as far as I can tell. This is the only reason I no longer install leaks, because WiFi Calling is very useful to me in my marginal-signal area. Once they do, I would expect it would work on the Z30 as well as the Z10.
    12-06-13 02:06 PM
  10. BBHermes's Avatar
    I believe T-Mobile supports WiFi Calling on all subscriber phones that are hardware capable of doing so, but if they don't sell the Z30 (I don't know if they do or not) the WiFi Calling app may or may not work. I'm sure there are T-Mo subscribers with a Z30 who could answer that question.

    It's not the OS per se "holding things back", but T-Mo hasn't released an updated WiFi Calling app that works with 10.2.xxx releases - at least as far as I can tell. This is the only reason I no longer install leaks, because WiFi Calling is very useful to me in my marginal-signal area. Once they do, I would expect it would work on the Z30 as well as the Z10.
    T-Mobile does not sell the Z30, which is why many of us were hoping to see wi-fi calling on an unlocked version. Preliminary reports are that it does not work on any unlocked z30's so far; some of us assumed it was a hardware limitation. Based on your point that TM needs to update the wifi app for 10.2.x, it would seem that, as long as the z30 is running exactly the same OS as the Z10 (sold and supported by TM) then wifi calling should work.

    So once 10.2.x is released for the Z10 in the US we can revisit the wifi calling thread for the z30.

    Thanks again to both raino and Jim for your replies and insights.
    Last edited by ishamid; 12-06-13 at 02:45 PM.
    12-06-13 02:31 PM
  11. raino's Avatar
    Checking my T-Mobile's Z10 box, the subvariant isn't printed on the label
    Are you sure?

    http://forums.crackberry.com/attachm...g_00000760.jpg

    (this is not mine, but from a different, recent thread.)
    12-06-13 08:53 PM
  12. DannyAves's Avatar
    Are you sure?

    http://forums.crackberry.com/attachm...g_00000760.jpg


    (this is not mine, but from a different, recent thread.)
    I don't see it on mine either.
    12-06-13 09:26 PM
  13. raino's Avatar
    I don't see it on mine either.
    I see. The one I've linked to isn't a TMO box but a factory unlocked RFK121LW. I thought they were all like that; I guess not.
    12-06-13 09:28 PM
  14. modifier's Avatar
    I see. The one I've linked to isn't a TMO box but a factory unlocked RFK121LW. I thought they were all like that; I guess not.
    Tmo prints their own boxes in white and pink. It's a waste. They might not have the sub variant on there. All US Tmo models are the 121LW regardless.

    Posted via CB10
    12-07-13 01:37 AM
  15. Jim Wolfson's Avatar
    Tmo prints their own boxes in white and pink. It's a waste. They might not have the sub variant on there. All US Tmo models are the 121LW regardless.Posted via CB10
    Correct, it's a custom T-Mo label printed on white sticker stock; I just double-checked and mine does NOT list the subvarient, but when I bought it I used the list of frequencies to confirm it's the 121LW version.
    12-09-13 02:44 PM
  16. nuangel2's Avatar
    I have an unlocked rogers z10.the variant is the RFF91lW. It came locked.i had it unlocked.i use it on T mobile without issue. I get 4 g and LTE.works great.

    Posted via CB10
    12-09-13 03:07 PM
  17. modifier's Avatar
    Correct, it's a custom T-Mo label printed on white sticker stock; I just double-checked and mine does NOT list the subvarient, but when I bought it I used the list of frequencies to confirm it's the 121LW version.
    The sub variant is on the main decal under the battery. It'll confirm that it's a 121LW, not that there's any concern. Just an FYI more than anything.

    I have an unlocked rogers z10.the variant is the RFF91lW. It came locked.i had it unlocked.i use it on T mobile without issue. I get 4 g and LTE.works great.
    Same here... both a 91LW and 121LW, each factory unlocked. No difference in signal on T-mo using 10.1.0.4780. I've switched to the 121LW and found it to be more reliable with wifi calling and wifi reception. Could either be updated hardware or because the OS is fresh.

    Posted via CB10
    12-09-13 05:52 PM
  18. Benjamin_NYC's Avatar
    So what sub variant is my direct from BlackBerry Z? Wifi calling works just as well as on my Q I got from TMO. We'll, actually I never used the wifi calling yet, but the symbol works lol.

    Posted via CB10
    12-09-13 09:37 PM
  19. modifier's Avatar
    RFK121LW, same as T-mo and Wind sells.

    Posted via CB10
    12-10-13 03:34 AM
  20. BBHermes's Avatar
    The sub variant is on the main decal under the battery. It'll confirm that it's a 121LW, not that there's any concern. Just an FYI more than anything.
    Posted via CB10
    Very useful FYI... Thanks! And if the BB store is selling the same Z10 shipped by T-Mobile, perhaps there's hope that when the BB store starts selling the Z30, it will work with TM's wifi calling frequencies as well (and by that time OS 10.2.1 will be on the Z10 in the US, lol).
    12-10-13 12:16 PM

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