Their original offer was free calling to landlines in 40 countries and cellphones in 6 countries. I have been enjoying that free calling plan for *eighteen months* which has been incredible.

Why does Truphone sound so much better than Skype and Fring? It absolutely does, just test for yourself and see how the other calls sound. The answer is *transcoding*.

Truphone uses the exact same AMR-NB codec as is used by GSM for calls. This means calls to cellphones are not converted from one small codec to another small codec, losing a lot of data in the process.

Fring does not use AMR-NB and the calls sound “furry” and much more quiet than the Truphone calls.

Skypeout calls; I won’t even comment; I’m sure many of you have had friends call you with it and you immediately know it’s VoIP. Variable rate codec as well – not sufficient for professional use.

Truphone’s AMR codec is a small codec (17-20 Kbit) so it fits over all sorts of tiny little internet connections you may have available to you, like DSL with only 64 Kbit upload – works fine.

How about really busy 3G networks that only have about a quarter of the expected bandwidth available? Works great.

I’m a bit shocked that nobody has dropped the Really Big Shoe which is that Truphone runs nicely over 3G – both UMTS and HSDPA.

I was talking to a new user tonight (I’m a bit of a Truphone evangelist) and he wasn’t very interested in using Truphone via WiFi because the 3G gives him great quality – why bother with WiFi at home when his 3G is already sufficient?

I’ve measured a one-hour call, and it used 21.2 megabytes over the 60 minutes. I get 250 Mbytes of data access for $10/month, so my cost in 3G data fees is about 85 cents per hour.

So even with 3G data fees added in, it still saves between 90% and 95% compared to my alternatives.

I make an average of about two hours a day of international calls via Truphone, from taxis, the mall, and via WiFi from my house. Call quality is really noticeably *better* than the normal international voice calls I receive or make.

Anil’s statement “It’s only for Mobile Phones which are connected to WiFi” is not true. Any E-Series phone or about four of the N-Series phones from Nokia will run it, over 3G. WiFi, while recommended by the company, is not needed.

My users here wonder why you’d use WiFi when the 3G is already indistinguishable in terms of quality. My answer is battery life; Truphone will run down the battery more quickly as it maintains a 3G connection all day.

So keep a charger at your desk.

Truphone is the most low-impact experience for the user – just select “internet call” instead of “voice call” on the handset when you call.

I have also tested Fring and Skype, WiFi to WiFi, 3G to 3G etcetera and IMO the quality is just not acceptable for anything but hobbyist calls.

I agree with Om and am a total convert. I never even bothered getting a fixed line or mobile plan. I only have a truphone number. Whenever I am not on Wifi (which is not very often), truphone automatically uses the backup SIM (which I can change like my underwear).

What I really hope for are more social features in the app and business features like conference calling. Also, the recent acquisition of SIM4travel will hopefully pave the way to getting a backup SIM that I dont have to change like my underwear…

Well done truphone!

Truphone uses some clever technology to make the phone automatically register using a known WiFi AP whenever it sees it – no user intervention is required. This appears to be achieved with little to no impact on the phone battery – brilliant!

Oh – and the voice quality with Truphone is outstanding. I have tried most of the alternatives (including Fring and Gizmo)with my Nokia N95, yet neither come close to thee quality that is achieved withh Truphone. Perhaps someone a little more technical than me can explain how/why this should be?