Taxibeat, an Athens, Greece-based taxi hailing app provider, is accelerating its international growth with $4 million in funding from the London-based venture capital fund Hummingbird Ventures.

The Taxibeat app allows customers to rank taxis and to hail specific taxis and drivers based on these rankings and their own preferences. For a commission on rides, Taxibeat also allows drivers to advertise the services they offer, for example languages spoken, the type of car and interior amenities.

Founded in 2011, Taxibeat initially raised $3 million from private investors. It now has services in Athens, Paris, Mexico City, Rio de Janeiro and Sao Paulo. Taxibeat plans to accelerate growth in current markets and expand into new markets in South America and Southern Europe, Nikos Drandakis, Taxibeat's founder and CEO, said in a statement.

Taxibeat said it serves $40 million in taxi cab transactions annually and is growing at a rate of 18 percent month over month. Its strategy is to launch in large taxi markets where quality of service and safety are difficult to manage.

Taxi transportation presents a great use case for mobile payments, Yankee Group mobile analyst Jordan McKee said in a blog posting. "Removing payments from the conversation when attempting to get from point A to point B provides considerable value in the form of convenience to the end user," McKee wrote. "When payment becomes an invisible component of the journey and the emphasis is on the overall experience, satisfaction results. We expect this to be a significant trend moving into 2014."

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