I acknowledge that. And I know they didn't just buy the app, but also the brand, the userbase, the marketing headstart, the team, the momentum.
But still. It boils down to a mobile app that could be cloned, bit-for-bit, for way under $5 million. Dropbox has a pretty strong brand of its own already. For instance: Almost everyone I know uses Dropbox. In contrast I have never heard of mailbox.app before. And I'm a nerd, I read Hacker News, I tend to know most of the fancy things before everyone else.
Ok, let's ignore that. Let's assume mailbox.app utterly dominates the (iphone?) market. What would it help them if Dropbox went against them with their clone?
Users are not exactly loyal when there's no network effect. I can't imagine mailbox.app would fare all that well against a (near identical) dropboxmail.app that comes bundled with whatever goodies Dropbox has planned to take it up with Google.
Sorry, I understand your angle (and your proposed strategy sounds plausible to me), but I just can't get over that number. Framing it as a long-term strategy for Dropbox makes it only more batshit insane to me, because even in my wildest imagination I can't see what mailbox.app brings to the table that Dropbox couldn't replicate for a fraction of the money in a very short timespan. And "fraction of money" means a difference of tens of millions of dollars here.
I expect the next moves to be either developing or acquiring media sharing (photos, videos, etc) apps
By that logic their next move will be to pull another Color.app?