Studio One 4 will allow you to use a touchscreen monitor. Below you will find some information on configuring them to work with Studio One.
You may want to visit http://musiccomputing.com/ if you are looking to purchase a touchscreen monitor.
If you are using the Windows operating system, the touchscreen functionality comes from the driver for your monitor. Windows has a built-in driver for handling touchscreen monitors, but many come with their own driver from the manufacturer. You will want to use the driver from the manufacturer if there is one that is provided.
To use multiple touchscreen monitors in Windows, the touchscreens have to be configured as independent touchscreen displays. This functionality must be supported in the driver from the manufacturer as the Windows driver may not support it. Contact the manufacturer of your touchscreen display for instructions on how to configure the system to recognize each touchscreen independently.
*Windows 7 does not natively support touchscreen monitors. If your monitor does not come with a driver from the manufacturer, you will want to update to Windows 10
On the Mac side of things, Studio One uses a 3rd-party program called TUIO for handling touchscreen monitors. Any monitor that supports TUIO should work for you. You will want to open Studio One and go to Studio One>Preferences>General>Touch Input. Here you can enable TUIO and set the monitor that is to be used. Here is a screenshot: