Skype URIs provide a simple way for you to initiate Skype calls and chats directly from websites, desktop, and mobile apps.
In its simplest form, you can embed a hyperlink referencing a Skype URI in a webpage to place a Skype call. For example, to initiate a call to the Skype Echo / Sound Test Service, the link would be
<a href="skype:echo123?call">Call the Skype Echo / Sound Test Service</a>
Clicking the link:
1.Brings the device’s Skype client into focus, starting it as necessary.
2.Effects auto-login or prompts your users for their Skype Name and password.
3.Typically opens a confirmation dialog to authorize placing the call.
4.Places the call.
More information on MSDN.
I will publish in the upcoming months information on the Skype URIs of Skype Development platform.
Please review the presentation introducing the new Skype for Business Developer Platform.