In Windows zooming is done by holding th Ctrl-key down and use the mouse wheel to zoom in or out. On a tablet you have to look in your documentation. Every tablet supplier has his own way to make the mouse wheel function working. For Apple you can look here http://alvinalexander.com/blog/post/mac-os-x/how-zoom-in-zoom-out-mac-osx-screen or here http://www.wikihow.com/Zoom-out-on-a-Mac.
The latest versions of the most known browsers should support the content of this site. The only browser that gives problems and unpredictable results is Microsoft Internet Explorer (IE). The lower versions (lower then version 9) don't handle HTML5 at all in a correct way. The versions IE 10 and lower are not any longer supported by Microsoft. If you want to use IE, version 11 is the only one. With Windows 8 Microsoft introduced a new browser: Edge. Their own advice is to use Edge instead of IE, which will also be discontinued in the near future. As the market share of Microsoft browsers (IE and Edge together is about 10%) we will only pay attention to Edge and leave out IE.
We have tested the following browsers:
Since the introduction of HTML5, there has been created a mechanism to cache each page you asked from the server. This has been done to make off line working possible and to reduce traffic with the server. The browser looks in the cache if a requested page is already there. If not, the request is redirected to the server. If there is a new page on the server and an old one in the cache, you will see the old one and you will get unpredictable results.
There is a lot of discussion about this topic on the Internet and solutions or work arounds. We have to look what is the best solution for our site. We are working on it!