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Microsoft CEO Satya Nadella admits giving up on Windows Phone and mobile was a mistake
(www.theverge.com)
This is a most excellent place for technology news and articles.
This was the downfall of BlackBerry as well.
QNX-based BB10 OS was phenomenal, and their hardware was top notch.
It was the lacking app ecosystem that killed it.
You need to read up on the fall of Blackberry. It was extremely badly mismanaged. It wasn't the lack of apps that killed them.
I was a BB developer right around the time of their demise. It never mattered how good or bad their OS was, because the development environment for BB was complete shit - which was a big part of why nobody wrote apps for it.