Mac Islayer and iStat Nano both come as free desktop widgets for Windows OS X. They can be used by anyone as they are user friendly, customizable and are extremely efficient in monitoring various aspects of your Mac. Both Mac Islayer and iStat Nano can be used to monitor multiple elements of your Mac such as CPU speed, Ram, hard drive space, network traffic, utilization rate, Temperatures, uptime and so much more.
The nice thing about istat Nano is that it can be used on any version of Mac OS X without compatibility issues. It works extremely well with both Carbon and Sierra. This simple little widget makes sure that you always have a complete and up to date stats on your Mac and can be easily removed and installed on a new Mac. This widget is very easy to install and run and gives you detailed information on all the vital metrics of your Mac instantly. The simplicity of installation is a huge bonus point and one of the main reasons why istat Nano and Mac Islayer are extremely popular amongst Mac users.
The other big difference between iStat Pro and iStat Nano is the user interface. iStat Nano looks very much like the standard apple iSCSI command line interface but with a few extra features. While this may not be enough for some people, it can come in very handy for those who need a graphical interface to monitor their mac's performance. The standard iSCSI command line interface is also compatible with many other operating systems including Linux, BSDI, windows and so forth. If you are still unsure whether or not to buy iStat Pro, then simply take a look at the performance numbers and user reviews!