LogMeIn
LogMeIn is a name you've undoubtedly heard of, becoming almost synonymous with remote desktop for the masses. Part of the appeal is how easy it is to setup new machines to access and start a session via the LogMeIn website, all without worrying about fiddling with networking or bypassing firewalls.
The business level product, called LogMeIn Pro, extends this with a native Windows or MacOS X app that makes it easy to maintain a contact book of machines and users, or take advantage of features like machine to machine file transfer without the need to start a remote session. On the collaboration front, multiple users can be given access to as single machine, or alternatively employees can allow other select users to connect.
Security wise all connections are mediated through LogMeIn's servers over SSL/TLS, where LogMeIn will then attempt to setup a peer-to-peer connection. If this isn't possible due to firewalls or other hurdles, it will fall back to a fully mediated connection through LogMeIn's servers.
Connection security is entirely via TLS and the negotiated level of encryption supported by host and client, up to 256-bit AES. Extra security features include generating a unique access code per host, random one-time codes sent from LogMeIn's servers via email, and protective features like screen blanking and keyboard locking on the remote machine during a session.
What's conspicuously absent is any form of central management for LogMeIn clients, though the company does provide a Group Policy template snap-in for the Group Policy editor that allows administrators to set LogMeIn parameters -- such as preventing file sharing, toggling remote reboot, and setting permissions for file transfers and printing among others.
Instead, LogMeIn sells a separate product called LogMeIn Central which among its many responsibilities as a general IT administration toolset can administer LogMeIn installations with a finer granularity of control. LogMeIn Central is the IT department's version tailored to remote administration, computer management, and advanced logging and reporting. However, as a separate cost this would need to be factored in to any deployment.
Operating system support encompasses Windows, MacOS X, iOS and Android only, however any gaps should be filled by its browser-based access that supports Firefox, Chrome, Safari and IE.
7. AnyDesk