Dropbox (NASDAQ:DBX) reported its first-quarter financial results after the bell Thursday. Here's a look at the highlights.  The Details: Dropbox reported quarterly earnings of 58 cents per share which beat the analyst consensus estimate of 50 cents by 16%. Quarterly sales came in at $631.3 million which beat the analyst consensus estimate of $628.67 million and is a 3.31% increase over sales of $611.1 million from the same period last year. Dropbox reported 18.16 million paying users for ...