Nokia apparently experimented with Android for Lumia Devices
This actually should come as no surprise, seeing how Nokia most definitely needed a Plan-B in case things didn't work out with Microsoft.
We’ve all wondered why Nokia didn’t go with Android instead of Windows Phone, but as it turns out, Nokia had secretly been experimenting with the Google made OS on their Lumia devices long before the Microsoft deal came through. However, now that Microsoft has bought out Nokia’s division responsible for producing the gorgeous hardware, those hoping to see Android on a Nokia device can lay their dreams to rest.
As it turns out, Nokia had the option of switching to Android in the later part of 2014 if they felt their collaboration with Microsoft wasn’t working out. According to some sources inside Nokia, the company had already started testing their devices on Android, quite possibly signalling that the partnership was not as fruitful as the Finnish outfit had thought it would be.
It turns out that some executives at Microsoft were also aware of the internal testing, and it could be that the acquisition of Nokia’s mobile phone and services was a bid to stop their most profitable hardware manufacturer from severing ties. Currently, Nokia accounts for 80 percent of all Windows Phone sales. While Samsung and HTC have also made Windows Phones in the past, the poor sales number of these devices seems to have deterred them from heavily investing in the platform.
While acquiring Nokia’s hardware and services business could be good for Microsoft’s own hardware ambitions, it would seem that going with Windows Phone eventually led to Nokia’s so-called downfall
Source: NYT