A computer mouse was probably the greatest human to machine interface ever invented. Sometimes though it is just not the right tool. Maybe your working on a task that requires more input such as a touchpad or you need more distance from your computer to make a presentation, etc. You can buy a touchpad that is fairly inexpensive, but then you have another device taking valuable desktop space.
If you have an iPhone or iPad there is an answer. Goonbee has a great answer…the Remote Keyboard + which is available in both free and pro versions. You can find a link to the Apple App Store at http://goonbee.com/apps/remote-keyboard. There are caveats to using your iPhone or iPad as a touchpad. You will need to have your mobile device and your notebook or desktop computer on the same wifi network. The notebook or desktop computer also needs to have a small application installed from the Goonbee web site. Fortunately the application download and installs quickly, and it does not take much in the way of resources.