Any body with an internet connection can talk free with anybody anywhere in the world, with quality almost equal to traditional telephone. Thanks to Skype that changed the way we think about making a call and other desktop messenger applications like Yahoo, MSN, Google Talk, Gizmo and some more that followed the suit. No longer we have to worry about expensive international call charges or for that matter even long distance charges with in countries. All is free or just a fraction of what you are used to shell out as long as you have an internet connection and a PC on both sides . This has completely changed the balance in the telecom world.
Now same ease and inexpensive way of calling any body in the world will be available to all of us right on the mobile phones. Next time when you make an international call on Mobile phone, you don't have to worry about counting minutes or scared of the heavy month end bill. Its as free as it is on the desktop. There a day comes, where you remember a user by his name to call instead of face less array of digits.
Skype has a mobile phone version that you can install on Pocket PCs (not on all mobiles at this time) and make calls directly from your mobile when you are at a hotspot or at home. Some wireless carriers like Hutchison 3 are installing Skype in the next set of wireless handsets that can work with both 3G and WiFi.
And now, Nokia announced support for Gizmo on thier N80 Internet edition phones. That means you can install Gizmo client on N80 series phones and can make cheaper calls, whenever you are around a hotspot or at home. Just like skype, you must be registered with Gizmo. Gizmo is free to talk with other Gizmo users and you must purchase minutes to talk to normal phones. Skype is free till the end of this year to call any number in US and Canada. Otherwise, you must purchase minutes at Skype as well. But rates are pretty cheaper compared with what you pay on your currently telecom/cell phone bill.
Though both Gizmo and Skype are similar, there is one difference technically. Gizmo uses standards based SIP protocol, that soon will also be used by all telephone/wireless operators. But Skype uses a proprietary protocol to connect calls. But for users, it doesn't matter as long as it connects. And compared to earlier SIP based implementations, Skype has been proved to be of much better sound quality even under seriously low bandwidth networks. That also means, skype has a better reach and experience than SIP based implementations like Gizmo.