In a blog post talking about technological improvements that were made in Skype to improve the overall experience over the last year, Skype team revealed that they are bringing synchronized chat message status across all of your devices. I assume with this new feature, you will be able to continue your conversation with someone exactly the same way across the devices at any points. Your unread messages, past conversations, etc, will all be synced.
Along with introducing support for Microsoft account in October last year, the Skype cloud also added the ability to queue and deliver chat messages even if the intended recipient is offline – so you can be ‘always reachable’ to the people who matter most. With Windows Phone 8 (and soon across other Skype mobile clients), this technology enables you to receive notifications when new messages arrive regardless of whether the Skype app is running.
We also know that people are engaging more and more with each other and with Skype across multiple devices at home, on the go, and at work so we are working to synchronize chat message status across all of your devices so you will know the current status of all of your chats on every device you use to interact with Skype. This capability will be rolling out across clients over the next few months.
Read the whole improvements from the link below.
Source: Skype Blog