One of Australia's fastest growing tech startups has raised up to A$39.5 million to further expand its global footprint.

Telecommunications and advertising startup Unlockd has also secured a partnership with Jamaica's largest telecommunications provider Digicel.

Digicel, is a similar size to Telstra and operates in multiple markets, its partnership with Unlockd could lead to further expansion throughout the Caribbean.

Unlockd engages consumers who view advertisements or other sponsored content on their phone's unlock screen to reduce their mobile data bills.

The company has over half a million customers in the US and Britain. It now plans to target the United Arab Emirates and Asia.

Its major advertising partners include News UK, Twitter, Yahoo, Facebook Audience Network and Dentsu Aegis, as well as brands like McDonald's, British Airways, Doritos and Lyft.

Unlockd was first founded in 2014 and has already raised more than A$420 million from a range of high profile investors such as Lachlan Murdoch Seven Group chief executive Peter Gammell, former Citibank managing director Jeff Emmanuel's PLC Ventures and Citibank Australia chairman Sam Mostyn.