Solar App 4+

This would be better as a widget. Download this and see what your LUX values are, but know that it will run the solar service whenever it is launched. The solar service will log excessively to your console log as others have mentioned. I plan to only open this occasionally, not let it install in my login items, and kill the solar service as soon as I am done with it. Logitech really needs to polish this up. Not a bad looking app and it does provide vital info that you cannot get elsewhere if you have a Logitech solar keyboard. Definately install it, but be prepared.

While the app does provide useful information, its overuse of the log files causes high load on the system, sometimes taking up more than 15% of system resources. Every keystroke or event results in a system log entry. While it doesn’t log the actual keystroke (or doesn’t seem to at least), it’s still a huge drain on resources. This results in overall system lag, and many times, keyboard lag. Until there is at least an option to disable verbose logging, I cannot give this app more than the 1 star.

You can get around the problem by opening Activity Monitor and choosing to quit the Solar App service. You shouldn’t have to use Force Quit, just a normal Quit. However, the next time you restart, it will be back again. I’m sure there’s a way to prevent it from loading (or just completely uninstall, which deleting the app doesn’t accomplish) altogether, but keep in mind, without the service, the status key won’t do anything, and you won’t have a way to determine battery capacity or the amount of available light to charge.

as all the other reviews have stated: it hogs your computer tremendously. I even followed the directions to permanently delete all of the application's files but somehow it was still running logs into Console. I kept searching everywhere to find where in the world are those logs coming from even after I had permanently deleted it's files. Eventually, I ended up in Activity Monitor and searched for everything directly related to the solar app and quit the processes. So far it has not given any logs into Console and everything is going much smoother. Delete the files and the processes on Activity Monitor to permanently stop it writing logs and make your computer run faster.
Other than that, the keyboard itself is really great.