answer:Dropbox is on the internet. On the face of it, it doesn’t make much sense to download something from the internet and then upload it to the internet again, so I figure you must mean something else. Does your phone not have enough storage to hold multiple ebooks? The largest ebook file I have is about 40MB (for about a 600-page textbook), and my last phone could hold about 100 of those- that ought to be enough for a 10-day trip, assuming you read 10 600-page books a day. There’s no way to make Dropbox’s servers download an ebook for you, unless you have special access to them (and if you were a Dropbox sysadmin I don’t think you’d be asking this question). Any such deal has to be done through your computer. There’s a bunch of ways to get your computer to upload ebooks to Dropbox automatically, and I won’t go through a long list, but you might want to try out the If This Then That dropbox channel or make your own recipe there.