Hi

Because our company has been providing long distance services in the US since 2002 and we have our own network and direct relationship with dozens of the world largest carriers, as well as network equipment on 2 continents. The cellular carrier from whom we get the SIM cards doesn't have as much influence as in the case of the other providers we've seen on the market who were only reselling SIM cards without much influence on the technical handling of the calls, and without any other revenue stream to ensure their service would be there for many years.

To save you from decompiling the cards, I can tell you that the SIMs are coming from an Israeli mobile operators. This being said, that does not mean it will encounter the troubles of other cards from Israel as the technical setup is completely different. 100% of voice calls transit over our own network.

We could imagine this SIP option indeed where you would send the calls to yourtelnamobilenumber@sometelnaserver . Would you need a proxy to register into, and/or are you sending from a fixed IP address?

Currently we offer numbers in California, Florida and New York. We will add shortly Washington DC, Nevada, Illinois and Texas

We don't pretend to have better rates than everyone else for all countries and we know that roaming to Canada or Mexico for example is a weak point for our service at this time. However we offer free voicemail online, which means that if you travel in one of the expensive countries with our service and you have access to the internet, you can check your voicemails from our website.

We understand that the missing text messages can be a deal-killer. We're working on making sure our US numbers properly receive text messages before rolling out the text messages service.

Thanks for your offer. A couple of questions...

Does your service require any kind of mnimum service period? That is, am I free to cancel anytime without being dinged a fee or another $49 yearly fee. Also, how easy is it to cancel the service, just sed email, phone call?

The service doesn't have any monthly fee, cancellation fee, trick fees.
All we have is an annual $49 fee, that we charge on the anniversary date of the SIM card setup.

So if you cancel before 1 year, then you pay no yearly fee if you used our upgrade offer. All you pay for are the calls you made.

Sending an email could be OK, as long as you make sure that someone replies that we took care of it (I'm saying this since sometimes emails can get filtered out in spam folders) or a phone call to our customer service during business hours.

Unlike most providers listed, we have a real customer service with live persons available during business hours in the US. And this customer service also helps our customers for regular long distance in the US, our customers for dial around service in the US, so we're not going to just turn off the customer service number like some other providers.

Do you run your own MVNO registrar or do you piggyback on your provider's HLR? Running your own registrar would allow the call path to entirely bypass the Israeli operator's infrastructure thus reducing latency.

To be compatible with the SIP world out there you must allow anonymous/unauthenticated calls to the client's SIP URI.

Can you also send voicemails to a specified email address?

We piggyback the calls to our provider's HLR.

We will then work on making this option available. As long as you send yourtelnamobilenumber@sometelnaserver to one of our IPs we should be able to add this feature.

For the voicemails we already have the option of a notification of new voicemail or notification of voicemail with the voicemail attached (wav file).

The call would come as a SIP INVITE from any source/URI to yourtelnamobilenumber@sometelnaserver.

Voicemails would be best compressed with either .gsm (limited number of players) or low grade single channel mp3 (to make it compatible with most email enabled phones out there). I for one use 16kbps/mono cbr mp3 to encode voicemails before emailing them to their destination.

Yes, SIP would be very useful. It would make it possible to bypass a chain of providers - thus provide better quality at lower costs. It would also make it possible to use your SIM as an extension of IP-enabled PBXes.

It would be also useful to have a DID from my own country. That number should also sent as CID when calling out.

As for me, I do not really need SMS, but a nice feature would be to be able to send SMS as if they would come from my main home number. Receiving SMS is free in most countries I visit, so I would be able to send SMS from one card, and receive SMS on another.

Latency is a key issue in these international callback systems. I recommended Celtrek service to a friend as being cheaper than using a Japanese prepaid in Japan. It was. It worked just fine. His wife refused to talk on the phone because she could not get used to the latency. When talking to her relatives in Japan, while in Japan, the call had to go around the world and back again. This introduced such a delay she couldn't accomodate to it. (Most people don't have a half-duplex mode.) Had they been roaming normally, the delay wouldn't have been an issue.

SIP would be very handy indeed. I could be called directly from a PC or even smartphone at any WiFi hotspot. It would also be handy to have options to call voicemail via SIP and/or receive voicemail as an attachment to an e-mail. The latter was a feature of Celtrek's initial offering which I used frequently, as I would travel out of cellular service for long periods of time but still have good e-mail access. I could receive my voicemails and then either e-mail the caller back or return the call via satellite phone.

gsm files shouldn't be a problem. I added this to the roadmap of future additions. MP3 I don't think we'll add it because it requires licensing of the codec.