It has been about three weeks since I've received my n900. I bought it to replace my BlackBerry Curve 8320. Despite my concern for the USB port's durability, I am pleased with the device and its capabilities. This time around, I decided to see whether it would be practical to use Skype for all my calls. I would like to share with you all my experience.

2/26: I order up T-Mobile Total Internet plan.

3/2: I receive the SIM card and promptly plugged it into my phone. So far, so good. To start, I bought an unlimited SkypeOut to US and Canada for $2.95/mo. After that, I forced the phone into 2G-only mode under the reasoning that 3G is available only in metro areas, if even that, and started calling up a couple friends of mine to test out the sound quality. While it was almost there, there was noticeable stuttering and unacceptable latency. I proceeded to switch back to regular voice service with Internet.

I am disappointed with the results of this experiment. However, my vision of VoIP on cellular networks has become much closer between now and three years ago when I first thought of such a notion. This experiment was a worthwhile exercise as it pushed the boundaries of what "normal" is. It is my conviction that humanity cannot advance without people who accept risks of doing something out of the ordinary.

I am keeping this device. I am not worried about whether we get MeeGo or complete Ovi Maps (although I hope for both). I am convinced that the Linux and open-source community have done good work and made many advances.

I wonder if you'd see an improvement in stuttering/latency if you switched back to 3G?

On 3G, the call quality was absolutely fine. However, I cannot assume that it is available everywhere. The 2G/2.5G test was done while stationary. I planned stationary and moving tests for this. Unfortunately, the stationary test did not pass, so I could not proceed.

Try a SIP provider instead of Skype.

Would 2G even have the bandwidth necessary for a VOIP call? I wouldnt have thought so.. It was designed for voice, and limited quality voice at that, and you want to pass data (with the packet information and routing protocol overheads added in) over it?

Don't bash the phone; youre up against a bandwidth limitation inherent to the GSM network design, using a technology froma time when the concept of internet didnt even really exist on PCs, let alone phones..

Seeing as a GSM call is on 2G and is essentially similar to a VOIP call I'd say yes.

@cashclientel: but the VOIP runs on top of 2 (or 3?) other encapsulation layers though, compared to the native GSM voice. That's smaller space to contain the actual payload, plus it would introduce higher latency and jitters.

@ysss: True - but you've got the option with VOIP to use a more modern codec, so could reduce the bitrate to lower than GSM and still have a perfectly audible call. Re: latency and jitters - again true... I'd be interested to test this though.

Skype on 2G is probably difficult, but some kind of optimised VOIP would be probably be ok if you had good signal.

Right...VoIP calls can be made with as little as 8Kb bandwidth, so 2G will suffice. But given that the OP may not have signed up for the "smartphone" internet plan, instead opting for the "regular phone" web2go plan, then it may be instant fail since the plan's designated APN seems to route all traffic via somewhere near Kansas. The smartphone plan seems to route traffic closer to the state/city where you actually are, at any given point.

Latency, at best, is already pushing acceptable limits @ 150ms, on 3G/smartphone, but backing down to lesser speeds, and "farther/more hops", let alone what Skype may have setup (test call voice has British accent...hmmm), you're gonna have some QoS issues.

I experienced similar results w/Skype as the OP, but faired slightly better w/my Vonage and callcentric accounts via the native SIP client.

Now wall penetration for T-Mobile USA's signal leaves much to be desired. That's a whole other issue.