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The Dream: Universal SIM Card + Universal Address Book

by Luca Filigheddu on June 25, 2009



The Dream: Universal SIM Card + Universal Address Book
Two cellphone SIM cards (bottom and top)
Image via Wikipedia

Think of this: a SIM card that offers you the lowest rate to call a local number in the country where you are roaming plus an “smart” address book that automatically gives a local number to your contacts, depending on the country where you are roaming. All of this should be seamless, all I have to do is just to upload my contact list with their original phone numbers into the address book and the software does the rest.

Am I asking too much? This is basically what you obtain by using a local SIM together with services like Rebtel or Jajah Direct. I reported my experience during my trips in the US months ago. The point is that you have to get a SIM card / plan from a local operator of the country where you are staying in order to achieve this result. Moreover, you have to manually assign a local number to the contacts you call the most, that is ok for me but not for many others.

If someone comes up with a powerful and smart solution like the one I mentioned above, please drop me a line ;-)

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Tagged as: cheap calls, luca filigheddu, Mobile phone, roaming, Subscriber Identity Module, Telecommunications, VoIP

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  • I think the address book isn't the issue
    I think what Luca is suggesting is a multi-imsi sim, not just a roaming sim
    So it has his home IMSI as a primary and a virtual IMSI pushed when he lands somewhere new
    Heard someone was working on that
    Not one or four countries, all of them
    Now what was the companies name again :-)
    (the phone book is already there as his numbers are in international format)
    plus of course, sync with my friends in Funambol
  • The solution that is closer to my idea is the one recently launched by Funambol and Jajah, but it works in Italy only and it makes sense for italians calling abroad very often. What you say about the virtual IMSI is the right answer.
  • Marek Gorecki
    Some time ago it was mentioned inbetween lines, that Funambol is working in cooperation with Jajah.
    Now they are going public - in a kind of Funambol chief national way.

    Yes, GoJajah app it is exactly this what I wanted to say in the beginning of this thread. I had (and still have) the same idea - but implementation based on neither Funambol sync nor Jajah terminations rates dependent.

    Luca, are they wrong with theirs minds of milions of local-SIM-based subscribers ?

    And keep in mind, that 'GoJajah-like' app can be repeated (in my project) on any new ( = e.g. from foreign country) SIM.
  • BTW, GoJajah is offered by Funambol and Jajah
  • Looks like GoJajah does this for SIM containing international phone numbers, but only if you stay in your own country.
    http://www.gojajah.com/
  • @Dean of course when I say "the SIM", I mean the operator's HLR ;-) I don't think you can't ignore the operator owning the SIM, the rate to call the local number is set by tha SIM's owner, you can't avoid it unless you use native VoIP, something I would not recommend for various reasons
  • @Luca - we may be at cross-purposes here. What I'm saying is that the SIM does not need to know, or do, anything - the phone can handle everything you describe, with an application. EG, that application need not reside in the SIM card.

    "the SIM must provide you with the lowest rate for a local call, regardless the country you are visiting"

    SIM cards do not do that. They have no awareness or least-cost routing capability. That's all down to the operator that owns the SIM, the HLR it's homed to and the routing behind that network operator. However, an application can know that, and can know the best local call rate number type for a given location (eg it can tell the SIM which number to call).

    The secret to the product you've described is 100% in the address book.
  • Marek Gorecki
    I agree all 'tricks' are done on address book (what I call contacts) level.
    This is pure (not so easy) technical, and can be done just once - and be repeated with all potential users.

    The other, in my opinion, much more difficult issue is how to provide appropriate SIM - with acceptable low rate.
    Of course one can think about this or that version of MaxRoam as one SIM for all countries - I believe it is doable, but very very niche product.

    On other hand - what if this solution would be offered for local SIMs ?
    For all foreign (travellers) users, but also to (counted in hundreds of milions of) local users ?

    Please comment.
  • @Dean - I mean, the SIM must provide you with the lowest rate for a local call, regardless the country you are visiting. The address book provides the right local number for your contact, then the SIM does the rest (plus the service that connects the foreign number, of course, like Rebtel or something).
  • @Luca - the SIM isn't the problem. The phone just needs to be aware that the SIM changed, have an awareness of it's location and have a data connection (briefly) ;)
  • Marek Gorecki
    Hi Luca,
    If you can accept, that you MUST use local SIM (because of number of reasons, which are far more important than inconvenience because of additional SIM to 'operate')
    - another, I might say brick-and-mortar-business-like issue of how to get local SIMs -
    the rest ('manipulation' around contacts) is almost ready.

    Almost, it means main part depending on 'internal resources' is done and tested.
    There is not much work left for external resources - matter of few k€ to invest and wait few weeks.

    Seamless operations guaranteed: no computer is neccessary - only mobile is enough.
    There will be no change in the way of calling - still:
    choose the name from contacts list and press green button.

    Market - do you see any limit ?
    Pricing - as you know termination can be really competitive to even eurocap roaming limits.
    With some dead simple tricks, depending on local tariffs (if there are free calls), termination may go down to zero level.

    Your turn ...

    //arekg
  • @dean the problem it is not the addressbook, but the SIM :-)
  • Luca,

    That's an application I could get built in a month (we've been doing a lot with address book sync lately so have some "tools") if you wanted to pick a single smartphone to launch it on.

    Ping me if you want to take it to market....

    Dean
  • Luca,
    I'm a big fan of MaxRoam, they seem to have the sim card part set up. As far as the address book goes, I don't know if we'll ever see that. I would actually like to see the address book standards revised, but that's for another time.
    Jeb
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