Skype is one of the leading service providers in the VoIP industry. VoIP stands for Voice over IP and it enables the user to use their Internet connection to make telephone calls or to do voice chat with the other users. Skype not only make computer to computer calling a possibility but also computer to telephone calling has been made a possibility by Skype. Skype offers free or very cheap voice calls over the internet and has gained huge popularity and success. Skype has moved out from the computers and has strongly put a hold on the smart phones. Various versions of Skype are available for installation on Smart Phones so that Skype calls can be made. Users have to login using their unique Skype user id and password and call to their Skype friends or other telephone numbers. Skype is being used on various smart phones including the iPhone.

On iPhone minimising Skype and working on other applications was not possible. User had to keep the Skype screen on top of all the other screens till now to work on it or to make or receive calls. But not with the release of new Skype version which is specifically meant for iPhone 4 minimising Skype while working on other applications is possible. User can make or receive Skype calls, put the call on loudspeaker and continue working on other applications on their Skype phones. This was not possible till now and users had to stay on the Skype screen and this stopped them doing some other work on their iPhone while talking on the Skype call. The new iOS4 compatible Skype client is smart enough and copes well with the multitasking capability of iPhone 4. iPhone 4 has already become the must have device in the US and is moving on the same trend in other countries as well. With Skype adapting themselves with the changes of iPhone will certainly lead to more popularity and acceptability by iPhone 4 users. Along with the usability Skype has also improved its interface quite a lot and has made it very iPhone like. The graphics of the Skype for iPhone 4 supports the Retina Display and gives a completely new touch to its appearance.

Skype is already facing tough competition with other VoIP companies like VoxOx and Google Voice. They provide same or better services and work on distributed server architecture. Whereas Skype has a single server to which a user has to login for making Skype call. It has one single database of users and this is being challenged by other companies who work on multiple servers. Other companies work like the conventional telephony system in which call is routed from one server to another but in Skype every call is established as a peer to peer connection hosted by the Skype server. On the other hand other companies use the standard VoIP protocol but Skype has its own protocol or technology for making the Internet calls.