1 2 Previous Next 15 Replies Latest reply: Aug 8, 2011 2:48 PM by mhschloss RSS

Unable to use Wi-Fi Calling while in Airplane Mode


Anyone have any idea why Wi-Fi Calling is explicitly disabled while in Airplane Mode,

even after Wi-Fi is reenabled?  This is on the G2.  My prior phone, a Blackberry Bold,

allowed Wi-Fi Calling when cellular service was disabled.  The reason this is important

to me is that I work in a building with little to no cellular signal.  I rely on Wi-Fi Calling

to allow me to make and receive calls on my cell number.  But I have noticed that the

battery lasts a lot longer when I have cell service disabled (Airplane Mode) even with

Wi-Fi enabled as compared to having cell serivice enabled and the phone constantly

trying to communicate with the nearest tower.


With the Blackberry, I could see T-Mobile preferring to use even a weak cellular signal

rather than Wi-Fi as cellular minutes were charged against your monthly allotment while

Wi-Fi Calling minutes were free and unlimited.  But on the G2, both Wi-Fi minutes and

cellular minutes are charged against your monthly allotment.


Anyone know if there is a configurable parameter somewhere that would allow me to

reenable this functionality?

  • 1. Re: Unable to use Wi-Fi Calling while in Airplane Mode

    Quick and dirty answer: You still require slight cell connectivity to permit the switch over to wi-fi calling. I will allow others to go into the finer points, but I imagine it is to do with proper registration of the G2 to connect via wi-fi. The only resolution I can think of in your case is, if possible, perform the switch while you have signals to both wi-fi and cell (for example, in a room where you do have both).

  • 2. Re: Unable to use Wi-Fi Calling while in Airplane Mode

    Perhaps I am missing something here but assuming that I have a location that has both Wi-Fi and

    cellular service, what would be the exact sequence of steps to configure this?  With W-Fi and

    cellular enabled, enabling Airplane Mode causes both Wi-Fi and Cellular to be disabled.  I then

    need to manually reenable Wi-Fi.  Once I have reestablished connectivity, any attempt to enable

    Wi-Fi calling is blocked with the message "Wi-Fi calling disabled in Airplane mode".


    And as for proper registration of the G2, why is it that a Blackberry can do this but an Android cannot?

  • 3. Re: Unable to use Wi-Fi Calling while in Airplane Mode

    I understand the desire to use airplane mode when cell reception is spotty, to assit with battery life. But, if wi-fi calling is enabled my assumption would be that an ongoing cell tower connection is unncessary, and therefore would not be a battery drain. In other words, perhaps give this a go without airplane mode being activated at all. See how the battery lasts.


    Again another assumption, but perhaps a Blackberry does make a cell connection even though you have selected airplane mode. It just doesn't explicitly show you it is making a connection to a tower. The one real test would be to switch to wi-fi calling when you are 100% sure you have no cell signal before you enter airplane mode.

  • 4. Re: Unable to use Wi-Fi Calling while in Airplane Mode

    the BB uses UMA technology which is different than wifi calling (although similar concept).  I see your point about putting it in airplane mode to save battery - good idea.  my only guess on why this does not work is to prevent people from using wifi calling on an airplane. 


    There may be an app in the market which would disable your cell radio without putting the phone in 'airplane mode'.  this may trick the wifi calling app into allowing the connection. 

  • 5. Re: Unable to use Wi-Fi Calling while in Airplane Mode



    Thanks for the suggestion.  But what you are asking me to try is exactly what I am doing right now.

    I am unable to use Airplane Mode and my battery life is not good.  The battery use diagram shows

    34% going to Cell standby while only 26% going to Wi-Fi.


    And I had used my blackberry without problem here in the same building and on an airplane in flight.


    Lastly, I am only able to enable Wi-Fi Calling when not in Airplane mode.  When I switch to Airplane

    mode it explicitly disables Wi-Fi and Wi-Fi Calling.  I am then able to reenable Wi-Fi but not Wi-Fi

    Calling.  That appears to be disabled in software.  Perhaps there is another app that can be used in

    place of Wi-Fi calling that allows making Wi-Fi calls while in Airplane mode.

  • 6. Re: Unable to use Wi-Fi Calling while in Airplane Mode



    Why would T-Mobile want to block Wi-Fi calling from a plane?  They allow it for Blackberry.  And they

    aren't blocking you from using it on a plane.  They are just blocking you from using it safely on a plane.

    One can always turn off airplane mode and use Wi-Fi calling while in-flight.  Seems that one could view

    this as encouraging you to violate FAA rules by using your cell phone while in flight and not in Airplane



    I guess that I can search for an app that can be used in place of Wi-Fi Calling.  But Wi-Fi calling uses

    minutes ($ to T-Mobile).  If T-Mobile forces me to use a 3rd party app then it is more likely that I would

    go with an app that does not use T-Mobile for phone service (i.e uses SIP instead) resulting in less

    revenue for T-Mobile.


    My assumption is that the Wi-Fi Calling app is provided by T-Mobile and the restriction is intentional.

    I just wonder why that might be.

  • 7. Re: Unable to use Wi-Fi Calling while in Airplane Mode
    Uma is not available for android.  It has nothing to do with tmo or charging for minutes.  It may just be the way the app is programmed that it does not work in airplane mode.
  • 8. Re: Unable to use Wi-Fi Calling while in Airplane Mode

    I'm gonna toss in the technical details of this.


    I had a Blackberry Bold 9700, my first UMA device. UMA is implemented thru hardware in Blackberries, since RIM has control of the hardware and software in a customer's hands. So RIM can implement UMA in a way that is ideal for usage, battery consumption (which we know is amazing on Blackberries), etc. Android DOES NOT have the necessary support for UMA in the software, nor does any hardware vendor for Android have the support in the chipsets for UMA. My understanding is that UMA is handled by a combined Wifi/GSM module on Blackberries for efficiency, reliability, and ease of use (not to mention ease of programming in RIM's case). 3G and UMA did not play nice on my Bold 9700, you couldnt do seamless transitions to/from 3G/wifi calling, the call would just drop if leaving a wifi network, or wouldnt hand off to wifi if on 3G. So, knowing this, Kineto, the makers of the wifi calling app on Android, came up with a solution that "just works" for Android, albeit you cannot transition into/out of a wifi network and expect the call to transition, it just will not happen. Here's how Kineto works: when wifi is on and Wifi Calling is enabled, Kineto FAKES to the cellular software stack in Android as if "hey, i have signal, and you can make a phone call". Therefore you CANNOT enable airplane mode, because then the "fake" cell signal can't be passed to the cellular software stack. The "need" for a cell signal in order for Kineto to register you onto a wifi network is 150% false. My partner lives in an area where neither AT&T nor T-Mobile have coverage (Though his iPhone 3GS fails to get a signal more often than my G2 DOES get a signal). I can confirm that with NO signal, from a cold boot, i immediately can register on T-Mobile using the Wifi Calling app, with no need for an initial cell signal before the handoff. So guess who gets to send texts, MMS, and make/receive phone calls all the time when over in that "no-man's land" for signal? Makes him so mad, all the time, since his iPhone can't even get an EDGE or GPRS signal.


    So hopefully that answers the question?


    Message was edited by: flamingblue8z for spelling errors, stupid Moto Xoom

  • 9. Re: Unable to use Wi-Fi Calling while in Airplane Mode

    Thanks, Flaming. Good to know.


    It would therefore stand to reason that if there's an app to disable cell connectivity, without having to enable airplane mode, wifi calling should in theory be an available option.


    A few days ago I had a quick look through the Market apps and found a number of power controls which suggested possible cell disablement, although they may have just meant data over a cell connection (2/3/4G), as opposed to the whole cell connection.


    On the other hand, if Android equates the cell connection being 'off' to airplane mode, then switching to wifi calling may never be a possibility.

  • 10. Re: Unable to use Wi-Fi Calling while in Airplane Mode

    Thank you, this makes sense, although I hope that someone is working on an alternative null cell

    stack that terminates above the hardware, for use when actual cell service is unavailable.  This

    would be useful for those of us in areas with poor to no cellular service - or for use in foreign

    countries when use of cell serivice is prohibitively expensive.  No signal really drains the

    battery and it seems silly that after a day at the office, using the phone for text and data

    exclusively via Wi-Fi, that Cell Standby reports as having used more power than Wi-Fi.



    One more question for you about UMA.  I seem to recall that UMA was also available in at least one

    non-blackberry phone - a fairly basic & inexpensive model if memory serves.  I can't find the

    webpage that describes which phones offer UMA (calls not using minutes) and which phones offered

    non-UMA Wi-Fi calling.  I assume that all Android phones are non-UMA and therefore calls are

    charged against monthly minutes.  Why did T-Mobile not charge for UMA minutes?  And if the hardware

    is built into RIM/Blackberry then why is it that neither Verizon nor AT&T have ever offered a

    similar feature for their Blackberry phones?

  • 11. Re: Unable to use Wi-Fi Calling while in Airplane Mode

    Exactly right, g2. It's in Android's code that you can't just "disable cellular network" individually like you can on a Blackberry. It's a shame, but it's just how the system is set up. Anyone who had a T-Mobile G1 when it first came out, like myself, would remember a time in Android 1.0, 1.1, 1.5 and I believe up to even 1.6, where you COULD NOT enter Airplane mode and then explicitly re-enable Wifi. It just didn't work that way, airplane mode turns off all "wireless" interfaces. It wasn't until 2.0 or later in the 2.x series (I believe) that Wifi could be enabled when in Airplane mode. But keep in mind, we are still at a time when Android is hard-coded to ALWAYS disable all connections when Airplane mode is enabled. Same is true of Windows Phone (I have an HD7). Blackberry is just nice enough to have 3 separate controls for cellular, wifi, and bluetooth, then an all-encompassing "Airplane Mode". And I'll tell you, it was SO cool to be on a phone call (in EDGE, nonetheless, not 3G, unless I was begging for the call to drop), turn on my wifi, wait for the call to hand over to UMA, then subsequently disable the cellular connection, all while the call continued over my bluetooth headset. That is the benefit of having UMA implemented through hardware. There may be a future where it is more pervasive in Android, but I don't see that happening unless more carriers adopt UMA/Wifi Calling (and I won't get into this AT&T merger, because I think they'd shut off UMA service altogether, honestly, since they have Fem-to-cells which make them money, whereas UMA is cost-free to us, and actually costs extra to them since they have to operate a separate network switch in their network backbone to handle the UMA connections separately from cellular connections, and in turn route the calls INTO the cellular backbone).

  • 12. Re: Unable to use Wi-Fi Calling while in Airplane Mode

    Wait a sec, mhschloss, you seem to have misread what I said (or maybe I misread what you said?)...


    In areas of NO coverage, you can IMMEDIATELY have Wifi-calling enabled and there's no problem, no necessity to have any sort of cell signal at all before connecting to Wifi. Let me provide another example: My in-laws live in Mingo County, West Virginia. It's the heart of WV Coal Country, the nearest cell tower from ANY provider, even Verizon, is a good 30 minute drive away. They don't even have cable available down there, just satellite TV/internet. I was able to use Wifi Calling down there to send/receive text messages while I was gone for a week. Back before I had a UMA-enabled device, I was off the grid for the entire time I was down there. T-Mobile could have had a nation-wide outage and I would never have known about it. Another example was the Snowmageddon of Feb/March 2010 here in Pittsburgh. 26 inches of snow fell so fast, I was trapped at my college campus in under an hour, and the power went out within the first 30 minutes of the heavy snowfall. 19 of T-Mobile's towers went out, but luckily the campus wifi network was powered by the backup generators, so I had service using UMA, when otherwise I wouldn't have had service at all, due to towers being out.


    Of course I could be misreading your response, in which case, my defense about this still stands: A "/dev/null" point for the cell network would be impossible, and possibly break many things in the process. Right now, I'm not too sure what those hypothetically could be, but I just smell problems arising from mocking an enabled cellular modem interface with a null point, when the real interface is actually disabled.


    To input about your "no signal" issue... I have fantastic "4G" HSPA+ 42Mbs signal in my house, yet I've enabled Wifi-Calling for the one "dead" spot that I fall back onto 2G, just in case of crossing that spot, so that I don't lose the call like I have a few times before (with many different phones). Even with my great signal strength, I still get a hit on the battery. There's little that can be done to completely shut off the cellular modem altogether, due to the radio firmware, the software telephony stack in Android, the actual Wifi and radio chipsets, and the Kineto app itself. As of right now, Kineto can be deployed to any of T-Mobile's Android handsets, as-is, with minimal per-device modifications. Most of those involve tailoring the app for each version of Android, as well as the difference in chipsets for Wifi and cellular radio, and how their driver implementation may be done in Android. There's a lot of variables, which is why Kineto's Wifi-calling took so long and is now put through quite a lot of testing before being placed onto the devices.


    As an aside to you bringing up about "no cell signal" at your office, it's important to note that enabling Wifi Calling makes your cell signal bars display "0 bars" of service, and in the Android system, it appears as if you have the very worse case coverage scenario, even if you acually do have service. Again, this is more of Kineto "fudging" things around a bit, just to make UMA possible on Android.


    Now, about the phones issue.... Nokia had a UMA-enabled phone, released around the same time as the Blackberry Pearl 8120, which was, I believe, the first Wifi-enabled/UMA-enabled Blackberry on T-Mobile. I could be wrong about the 8120, but regardless, Nokia had at least one UMA-enabled phone, Samsung had the Katalyst, and there was at least one Sony Ericsson. At the time, however, UMA was implemented through hardware-only. There was no attempt to create a software UMA implementation. Wifi-Calling (which is just the software form of UMA), was not introduced until last fall. So every handset prior to last fall was Hardware UMA only, because at the time they wanted reliable hand-offs back and forth from cellular to UMA. So indeed, to an extent, all Android phones are "non-UMA", though to be more appropriate and make it easier for all to understand, it's software implemented UMA.


    The billing aspect is another issue altogether, because UMA, hardware OR software, all runs through the same server. It is all billed the same. Back when Hardware UMA was the only implementation, they offered, as a bit of a promotion, to have it not hit your allotted minutes when using UMA, for $10/mo. That eventually went away a few months prior to the Wifi-Calling app being introduced in the G2's OTA and on launch of the MT4G. It was just in these past few months that a new feature was re-introduced, for free, where all calls carried on Wifi-Calling, would not deduct from your plan minutes. There's a major reason for this difference, and it deals with billing. Since Wifi-calling on Android is a software implementation of UMA, and is limited to calls only being able to originate and terminate on wifi, therefore can't be handed over to cellular, there is little reason for there to be any billing discrepancy. However, the hardware implementation of UMA can hand off to cell towers, and back to wifi. So, how would T-Mobile bill a call that originated on UMA, transitioned to cell after 10 minutes, then 2 hours later, transitioned back onto UMA, where the call terminated a further 15 minutes later? That's why there was a $10/mo fee back then to enable to feature, so that they could recoup any billing errors that were in the customer's favor. I know that the new feature MAY still be available, it was for Even More/Even More Plus plans AFAIK, you could request to have it added on, and it is free, but only on select plans. I have had Unlimited Loyalty for a few years, so I stopped counting minutes a long time ago.


    Oh, and finally as for VZW, AT&T, and Sprint... They haven't implemented UMA for a variety of reasons, mostly involving money, undoubtedly. T-Mobile has always had Deutsche Telekom to back them up, financially, in their endeavors over the years. "HotSpot Calling", aka UMA. "HotSpot @Home", later just "@Home", and now discontinued. I'm still kinda mad cuz I have a T-Mobile router and used @Home a lot. The @Home service was actually UMA inside a router. The router took a SIM card, and everything was handled over the internet, and you hooked up your home phone to the router. Simple as that. I miss my @Home some days. From my understanding of what the UMA "interest group" or whoever sets out the UMA guidelines (I think 3GPP), I believe it's exclusively a GSM technology (that kicks Sprint and Verizon out real fast...). In AT&T's case, I can't explain or begin to wonder why they weren't concerned with UMA. If you look at the time-line, Cingular was still around when UMA was introduced by T-Mobile, then the iPhone came out, AT&T switched Cingular over to them, and really there was just too much going on for R&D and Network engineers to worry about "how could we make this work?" At the end of the day, AT&T came up with the idea to use Fem-to-cells, $150 mini cell towers you plug into your router. And then they charge you a monthly fee for using them (or used to? I haven't kept up on that saga over the years). Keep in mind, UMA requires T-Mobile to continue operating a large network node just for UMA to operate. Servers, network switches, backbone to receive the incoming UMA calls from the internet. It's all pricey, but it saves money on operating costs of the towers, not to mention frees up the airwaves and tower bandwidth for users who ARE using the cell network.


    Finally, AFAIK, the only Blackberries that had a UMA-enabled chipset were the models that explicitly were designed for UMA-enabled carriers. Example: I had a Bold 9700, and I knew someone with an AT&T Bold 9700. His had the AT&T 3G bands, mine clearly had T-Mobile's. There were different chipsets in his 9700, which did not include UMA functionality, but the overall software in a Blackberry is actually designed to target each chipset that was put into that model for each carrier, and the Blackberry OS determines what features to enable (which includes whether or not to show specific carrier-dependent apps) based on what carrier your phone is designed to run on.


    Long-winded, but hopefully that answers EVERY possible question about this issue!

  • 13. Re: Unable to use Wi-Fi Calling while in Airplane Mode

    Figured I should add this, after some Google searching, I found this article from August 1st, 2006 on Engadget Mobile:




    And here's the Nokia 6301 and Samsung t339 announcement



  • 14. Re: Unable to use Wi-Fi Calling while in Airplane Mode

    I found this while searching for information about using wifi only while on a trip to Canada.


    Apparently the wifi calling app you're referring to is T-Mobile's own, right? Does Google Voice have the same problem, or would it work? (I currently use it for SMS, as well, which would be nice to be able to use with wifi only.)

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