This was a temporary logo. They changed their color from "Nokia Blue" to purple (same color as 2014 Microsoft Band logo) and changed it's font to Segoe UI. It was used commonly on Microsoft Lumia's social networking accounts like Facebook.
They replaced purple color with cyan that uses the same color as Microsoft Surface and added Microsoft Logo. In October 2017, Microsoft Lumia has discontinued because Lumia's sale had declined.
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