Microsoft has launched Skype for Mac 6.4, a major update of its Skype chat platform for OS X users. Version 6.4 is focussed on improving Skype’s instant messaging features for better usability, while also introducing support for Simplified Chinese.

Version 6.4 adds infinite chat scrolling, a feature already present in the Windows build. This allows users to load historical conversations simply by scrolling upwards. This action simply loads messages from the chat history stored on the user’s computer.

If users find this too tedious, they can pick a point in history to jump back to, simply by right-clicking or [Ctrl]-clicking anywhere in the chat window and selecting Jump Back followed by the period they wish to skip back to, with incremental choices from one day to a whole year all available.

Improved bulk sharing of contacts is one of Skye for Mac 6.4’s many improvements.

To help make the chat history easier to navigate, Skype for Mac 6.4 also separates dates from timestamps, and will index all the chat history when first logged in, which enables it to consume less resources once indexing completes.

Version 6.4 also sees the find function redesigned to display results in the main chat window as opposed to opening a separate one, with the total number of matches highlighted. Recent search terms are stored for easy retrieval, and users can now search using “Starts with” and “Contains” as search parameters.

Other enhancements include improved file transfer, allowing users to reaccept a file when receiving, leaving the file transfer active until the sender cancels it. Contacts are now sent and received differently too, allowing multiple contacts to be received in a block, or accepted one by one. Any existing or blocked contacts in the list are also clearly marked.

Version 6.4 has removed the Custom Chat Styles feature to promote consistency with other platforms, but users are encouraged to choose Preferences > Messaging > Use Compact Chat Style if the default layout is too large. It also drops support for OS X 10.5 (Leopard).

Skype for Mac 6.4 is available now as a freeware download for Macs running OS X 10.6 (Snow Leopard) or later. Other available builds include Skype for iPhone 4.6, Skype for iPad 4.6 and Skype for Desktop for Windows users.