ViewTouch is the ONLY point of sale solution which is designed to run 100% on the network, 100% on Linux, and 100% on the Internet's protocols - TCP/IP - transmission control protocol / Internet Protocol.
ViewTouch point of sale software does not rely on the legacy PC architecture in which computers sit on the network and use the network to pass data files & print jobs among themselves. Instead, ViewTouch broadcasts point of sale screen information directly to the touchscreen displays which are attached to the network. ViewTouch broadcasts your POS screens to touchscreen displays located anywhere on the Internet, too, and no other point of sale solution does this in a straightforward, secure way. You have the ability to access and control your POS system from anywhere on the Internet, without the need for any third party software applications.
ViewTouch runs very nicely on the Raspberry Pi.
Click on this picture of the Raspberry Pi to download the image to your linux computer, then copy the image file to a class 10, 8Gb microSD card for ViewTouch on the Raspberry Pi with this command: ddrescue -f /path/to/imagefile /dev/sdb
Note: Not every microSD card will allow this image file to be written correctly to it. I used a Sony microSD card to write this image. If you will tell me what your results are with various 8Gb microSD cards are I will build a list of those which work and those which don't work. Fry's Electronics has these microSD cards for $8.99.