Spark Payments is an external terminal application for processing DASH transactions in brick and mortar stores. Using InstantSend transactions (secured by Dash masternodes) makes things very quick.
This method of processing transactions is compatible with Square, Clover, etc. and other existing POS software. Merchants can easily incorporate this into their existing workflows.
Spark currently supports 94 currency exchange rates, 11 languages, and instant fiat conversion through uphold.com