We have an application that allows you to add and edit items to your SAM4s SPS-520R or any of the SAM4s SPS-500 series registers. We are using a commercial windows tablet but no reason you could not use a Surface or something like that as long as it is Windows. Wtah the video below where I add an item to the cash register database over Wi-Fi.
If this is something you want to add to your SAM4s cash register give us a call at 800-863-2274 or visit our site Wireless Data Collector for the SAM4s SPS-520R cash register