If you are looking for MOBILE printers, the level of documentation and standardization is reduced. Most will do partial support of some Epson standards but they usually have their own protocol to utilize their printer configuration to the maximum.

If you have some development money to spend... you call the mobile printer company and request a developers package. Some companies will sell reduced cost models supplied with additional manuals to assist developers. But the manuals are usually poorly written.

-Jay C. Box