Mobile email client Mailbox has announced taking its 1 millionth reservation, as it moves into its new offices at its new parent company Dropbox.

The app was released to much fanfare just six weeks ago. In order to take its time scaling, Mailbox initiated a unique reservation system that showed interested users how many people were ahead of and behind them in line. The company told customers who have yet to get in to “stay tuned”, while reassuring that its line “continues to get faster every day”.

Also marking the occasion, Mailbox released an update to its app, adding the ‘shake to undo’ feature. The new software also includes UI enhancements and bug fixes.

shaketoundo mailbox Email app Mailbox hits 1M reservations filled as it moves into its new office at Dropbox

Dropbox swooped in to acquire Mailbox and its team last week for an undisclosed amount. While some rumors had suggested the deal went down for as much as $100 million, Mailbox’s first and largest investor noted only that he was “thrilled” at the sale and there had been several other parties interested.

While Mailbox’s public reservation system certainly served to attract interested investors and acquirers, it also demonstrated the company’s own need to partner with a bigger company in order to ramp up. Mailbox relies on its own servers to process email, so each additional user requires additional resources. At this point, the company is at risk of losing interested users who get tired of waiting and turn to other email solutions that are also picking up steam.

Headline image via Thinkstock

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