I have been using droplr for quite sometime now and it is good but it lacks synchronization. If you could recommend other service, what would it be?
For sharing of 1 (big) file with multiple people I use WeTransfer.com. For sharing between multiple computers / mobile devices I still think Dropbox is the best. Sharing folders for collaboration also works really easy. If you are looking for a lot of storage Google Drive might be better because the storage is cheaper. It also works on most devices and synchronize really well. I've tried SkyDrive but had some synchronization problems.