Dropbox was as much about the market being right as good execution. If 90% of people only use one device, there's little need for synchronization. Dropbox did s

Dropbox was as much about the market being right as good execution. If 90% of people only use one device, there's little need for synchronization. Dropbox did sync right, but also coincidentally at the same time that netbooks and smartphones were making sync a valuable mass-market product.