Of course, Agent and Viewer for Mac are already in development. The release of Agent/Host for Mac will follow the Viewer for Mac which we hope to release by the end of the year. Unfortunately, we cannot provide any specific ETA yet.
As for the Host/Agent for Mac/Linux - we plan to release it this year, but, unfortunately, we cannot provide a more specific ETA on it yet. Hopefully, we will be able to release the first beta in a few months. However, we will make sure to notify all our users when Host/Agent for Mac/Linux is released. Sorry to keep you waiting.
I have brought 3 starter licenses. 2 of them are installed in windows platform for viewer and host but third I want viewer on mac and host on windows which is already installed. What Needs to be done Pls. advice if the same key for third installation can be done on mac book pro.
Please note that your license key is not restricted to a specific workstation even if it's a 1-tech license key. For example, you can register two Viewers on different machines if you plan to use them one at a time, so yes you can use the same license key to register Viewers on Windows and Mac as long as these Viewers are not used simultaneously. For more information please see this page. Here's also a guide on registering Remote Utilities just in case if it might be useful.