By Daily Mail Reporter PUBLISHED: 21:42 EST, 27 May 2013 | UPDATED: 07:12 EST, 28 May 2013 When it comes to designing apps, the hope is usually that your program will not only be useful to people but that you might also be able make some money as a result of its creation. For Gentry Underwood, his wildest dreams were realised when his Mailbox app was sold to Dropbox for $100 million. The app wasn't even available to the public, only by joining a mailing list. The Mailbox app allows users to organise and clear their email inbox in a far more smartphone friendly way than previously available.
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Gentry Underwood says he designed Mailbox to 'make email easier'
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App was sold to Dropbox 37 days after Mailbox launched
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Users can view both their inbox and most recent open email at same time
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Being bought by Dropbox was 'logical' as the company deals with sending large files
'You can imagine Mailbox going to some company that monetizes through advertising, where over time we’re going to have to find ways to put more and more ads into @placeholder — things that might actually decrease the overall experience or invade a user’s privacy.