As voice over Internet protocol (VoIP) services, Line 2 and Skype both allow users to send voice data using Internet data packets, instead of using a traditional public switched telephone network. While Line 2 provides more calling features than Skype, making it better-suited for professionals, Skype -- unlike Line 2 -- allows for free basic calling features, making it a better fit for users on a budget.
Skype Limited released the first public version of the Skype VoIP software in August 2003. The company designed the Skype software for face-to-face video calling between computer-users. However, in 2009, Skype Limited released an iPhone application, which extended the reach of Skype into the realm of smartphones. In comparison, Toktumi Inc. released the first public version of Line 2 in January 2008. Toktumi designed the Line 2 software specifically for use with Apple iPhones. Line 2's interface "clones" or replicates the iPhone's interface, which means Line 2's dialling pad, recent calls list, voice mail menu and contacts list look identical to those of the iPhone.
Unlike Line 2, Skype's primary services are free to use. These services include one-to-one video calling, instant messaging and screen sharing. However, accessing more advanced Skype features, such as calling phones and call forwarding, requires a paid subscription or pay-as-you-go plan. Paid Skype subscriptions start at 1.2-cents per minute, while pay-as-you-go plans start at 2.3 cents per minute, as of 2011. Users can also purchase Sky Premium for £2.90 per month, which includes group video calling. In contrast, using Line 2 always requires a fee. While the "Standard" package, which includes phone calling and a standard phone number, costs £6 per month or £64.6 per year; the "Professional" package, which includes a virtual attendant and a toll-free number, costs £9 per month or £97.1 per year.
Line 2 offers more features for enhancing call convenience and functionality in comparison to Skype. For example, unlike Skype, Line 2 provides call waiting, for switching between two live calls; and conference calling, which allows up to 20 people to simultaneously communicate via the Line 2 application. In addition, Line 2 allows users to decline incoming iPhone calls without having to drop a VoIP call. In contrast, if a Skype user declines an incoming iPhone call, the VoIP call will be lost.
Skype and Line 2 both allow users to place calls over a Wi-Fi connection. Joining a Wi-Fi network requires that a smartphone be within range of a wireless router. However, unlike Skype, Line 2 also supports third-generation (3G) connectivity, which utilises cellular networks that divide large geographic areas into smaller units or cells. By sending and receiving signals over different cells, Line 2 can remain connected to the Internet and support VoIP calling functions regardless of changes in location.