There haven't been many happy moments over the past five years for Finnish smartphone player Nokia (NYSE:NOK). Although Apple and Google have changed the game in the smartphone space since 2007, Nokia has been slowly eyeing a return to relevance with its flagship Lumia line of smartphones. In fact, the company gave investors a bit of a shot in the arm last quarter, when it posted stronger-than-expected Lumia sales in its most recent quarterly report. However, this encouraging number doesn't have everyone impressed. In this video, tech and telecom analyst Andrew Tonner warns investors that booming Lumia sales could contain a hidden bomb.

Fool contributor Andrew Tonner owns shares of Apple. Follow Andrew and all his writing on Twitter at @AndrewTonnerThe Motley Fool recommends and owns shares of Apple and Google. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.