The deal with AEVI will see the Edinburgh-based firm's scheduling and booking software being made available to more than 500,000 firms worldwide.
The software will feature on AEVI's cloud-based suite of business-to-business apps and services.
From February, users will be able to schedule appointments on AEVI-enabled point-of-sale devices.
Appointedd's software is designed to help small and medium sized businesses (SMEs) make appointments with colleagues and customers wherever they are in the world.
Appointedd was founded by Leah Hutcheon in 2011 and has attracted support from several high-profile investors, including Skyscanner founder Gareth Williams and Macklin Enterprise Partnerships founder Marie Macklin.
Ms Hutcheon, said: "At Appointedd, we're passionate about supporting businesses to grow and flourish and this new partnership with AEVI exposes Appointedd to a wide range of businesses across the globe, enabling us to help them to scale their businesses.
"We know that SMEs are short on time and Appointedd can help them streamline processes, grow their businesses and gain a competitive advantage."
Online booking firm Appointedd has formed a strategic partnership with a global payment transaction provider.