An e-mobility service provider (eMSP) is a company offering customers access to charging stations by using a web or mobile app that connects their car to the charging network. The app shows available charging points and also manages payment for charging sessions.
These are the minimum services of eMSP companies. They could be doing other things as well, such as building customer loyalty through a rewards scheme, offering EV roaming to non-network charge points, and clarifying which charging stations use energy from renewable sources.
One quick note:
The EV industry is evolving rapidly, even at the level of spelling. We use a few terms and spellings here intentionally, such as e-mobility, electro-mobility, and eMSP. All of them point to the same thing: the business that connects drivers and their vehicles to the EV charging operator via an app.