First a disclaimer. This is not easy to set up. I like to think I am a tech savvy kind of guy and it took me several hours of research to get it all working smoothly.

That said, it is worth the effort and once it is set up it is seamless and transparent. You dial a call. It rings and connects. Someone calls you. It rings and connects. No one has to do anything special.

What you get. 100% FREE!!!!! VOIP SIP phone calls both incoming and outgoing on your smartphone to/from any US number completely transparently and did I mention FREE, any place you have any kind of data access. It works on WiFi, it works on 3G data, it even works semi-OK on EDGE. From any place on the planet. Someone dials your US number, your phone rings and the other party is none the wiser as to where you are. You dial a US number and it rings irrespective of where you are. IT DOESN'T EVEN USE ANY OF MY PLAN MINUTES HERE IN THE US!!!! Because all the calls are transported over my unlimited 3G, not the cellular network.

Just like Vonage or Skype but with the major exception, it is completely FREE and requires no PC!!!!!!!

What you need. A smart phone with data access of some sort. I have it set up on an Android phone and also on a cheapo WiFi SIP phone but it should work fine on I-What's, Blackberry's, certain Nokia's, dedicated SIP phones or adapters, et al.

The basic rundown.

1: You need to sign up for a free "Google Voice" account at http://voice.google.com.

2: You need a free Gizmo5 "call-out" account from http://www.gizmo5.com (if you are lucky enough to have one already, alas they are closed to new accounts at the moment)

OR

You need to get a free "SIPgate One" account from http://www.sipgate.com/

3: You need a free "SIP Sorcery" account from http://www.sipsorcery.com

4: You need a SIP app for your smartphone OR another SIP compatible device. I used the free SIPDroid app from here http://www.sipdroid.org/ on my Android phone. (download the apk from the web site and install from your SD card. Don't use the version in Market because it is disabled on 3G and EDGE to appease cellular companies). For I-What's, Fring is the recommended app. Blackberry's I'm not sure, but I know there's an app for that. Certain Nokias have SIP capability built in. There are also a whole host of hardware SIP adapters and SIP phones.

Now the hard part. See disclaimer at the top of this post. How to set it up is beyond the scope of a post on a whore mongering board. There is an excellent how-to here.

http://docs.google.com/Doc?docid=0Ae8glDUXDsh9ZGR2eG43cjRfMzNkOTM4ZjNjeA&hl=en

It is however not comprehensive and will need adapted to your specific SIP app. Research, research, research. Google is your friend.

Local guys who I know, I will help set it up if I'm around sometime. I can answer specific questions here but try to do allot of the footwork yourself.

An added bennie if you are lucky enough to already have a Gizmo5 account is you can also set that to forward incoming calls to a foreign SIM card at your expense at very reasonable prepaid rates so if you are in the field overseas WITHOUT data access and someone dials your US number, it will transparently forward the call to your foreign cellphone number, charge YOU 10 cents a minute or so from a prepaid account and the calling party knows nothing out of the ordinary but that they called a US number, it rang a US ring tone, and you answered the call. Still might be hard to explain the blaring foreign techno music in the background though.

(Message edited by I_am_Sancho on May 08, 2010)

(Message edited by I_am_Sancho on May 08, 2010)

I might have to add, I had it working 100% perfectly with the above set up using Gizmo5. But while deliberately causing bad EDGE connections to test it's performance under adverse conditions I decided I would do better using a low bandwidth codec. Problem is, Gizmo5 supports several low bandwidth codec's and the SIPDroid app I am using also supports several low bandwidth codec's but.... not the same low bandwidth codec's as Gizmo5. So I was stuck with using high bandwidth codecs on EDGE which results in choppy performance on EDGE connections. So I decided to try SIPGate instead of Gizmo5 just to see if they had a more compatible selection of low bandwidth codecs. There I ran into a problem of T-Mobile blocking incoming data on the relevant port resulting in no incoming audio at all. Undaunted and unwilling to have choppy performance under EDGE I came up wit a workaround adding ANOTHER piece to this already insanely complex setup.

Solution to achieve good performance on EDGE using low bandwidth codecs. I opened a FREE account on pbxes.org, created a trunk that routes calls between my phone and sipsorcery. pbxes.org has a wide variety of codecs available including an excellent low bandwidth codec and will translate before forwarding it to sipgate or Gizmo5 and in addition they offer several ways to defeat ISP's blocking VOIP and further strategies for dealing with packet loss or other network problems.

Setting up the pbxes.org part was brutal. There is nothing user friendly about it. Did I mention this is a difficult thing to set up.

But adding that layer to the cake made a huge difference under adverse network condition. It is now completely reliable even under EDGE or ISP blocking. It is still 100% completely free. Now that it is set up it is as simple as dialing any phone call, the setup is rough but day to day operation is transparent and no different than making any call.

I also modified the script in sipsorcery to use either or the Gizmo5 account or the sipgate account providing redundancy should something break down or fail along the way. You dial my number and their are two separate services trying to ring my phone.

This is REALLY hard to set up but once it is set up it works beautifully.

I fancy myself as kind of a tech nerd and this made MY head spin. Kudos to you for figuring it out!

EA

I feel like I have acquired a PHD in SIP VOIP over the last couple of days setting this all up. It was hard. The 100% free calls and 7/24 availability anywhere on the planet is pretty cool but a more tangible benefit is I am now confident I have learned enough to set up a business class VOIP PBX from scratch at the office. Management has recently spoken with several commercial VOIP providers. IMO their offerings were insanely overpriced and management has not moved forward based primary on that opinion. Right after my next trip I will present a proposal that I build the entire system replacing the free components of this system with appropriately priced business class components and at the same time add features like desktop delivery of voice mail and integration with smartphones of sales reps in the field. I figure I can easily deliver $20k-$30k/year savings on the companies phone bill AND cause the sales reps to be overjoyed by their new found capabilities. I feel a big raise coming from all of this.

Man, this looks very awesome. Eventually, I will give it a try.

After extensive experimentation with various codecs I settled with the Speex codec http://www.speex.org/ as my primary transport for both high bandwidth and low bandwidth/packet loss situations. In my real world testing it is clearly superior to the other options. This codec only works with the pbxes.org layer added to the cake but with it in place I feel confident my Android phone can laugh off wayward packets that never make it out of the third world. Only 11 kbit/s required to maintain a quality SIP call. That should even work good if I find myself someplace with no 3G and no EDGE and 'gasp', only GPRS.

A more user friendly guide here.

http://forum.xda-developers.com/showthread.php?t=548405

I just saw this. I haven't reviewed it 100% but at a glance it looks like more or less the steps I took with a few adaptations but since it has arrow's and pictures it is certainly probably much easier to follow.