A team within Nokia had Android up and running on the company’s Lumia handsets well before Microsoft and Nokia began negotiating Microsoft’s $7.2 billion acquisition of Nokia’s mobile phone and services business, according to two people briefed on the effort who declined to be identified because the project was confidential. Microsoft executives were aware of the existence of the project, these people said.
Of course, one would expect Nokia to have a plan B in case it ran into trouble with Windows Phone. Getting Android running on the Lumia was not a Herculean engineering effort, according to their source.
Notably, Nokia had an option to exit its partnership with Microsoft at the end of 2014 and may have used the threat of switching to Android as tool in its dealings with the company.