Introduction to TinyMCE.
TinyMCE supports most modern operating systems and browsers. Some examples are: Mozilla, Internet Explorer, Firefox, Opera, Safari and Chrome. TinyMCE has a large userbase and an active development community.
TinyMCE is the default visual editor since Plone 4.0.
Browsers on mobile devices were, until recently, limited in their support for editors like TinyMCE. The situation is improving all the time. If your mobile device supports installing different browsers, it can help to check if modern browsers like Chrome or Firefox give better results when working on a tablet or smartphone.
Updating to the latest version is usually a good idea.