Shake, drop, carry
The gesture is the whole product. Start dragging anything, wiggle the pointer, and a shelf spawns under the cursor. Let go and the item sits there. The drag you were failing at is now finished, and finding the destination is a separate job you can take your time over.
The shelf holds more than one thing, and it holds different kinds of thing. Files from Finder, images from a browser, attachments out of Mail, text you selected. You can keep adding to an existing shelf, which means a set of files scattered across four folders becomes one pile you assembled at your own pace.
Getting things out is drag-and-drop again. Pull one item, or take the whole shelf at once. In the version I have there are extra actions on the shelf too, including AirDrop and compressing the contents, though the plain carry is what I use nine times out of ten.
It is on the developer's own site at dropoverapp.com and on the Mac App Store. I am not going to quote you a price, because I would rather you read the current one there than trust a number in a blog post.
What it actually replaced
Before it, my method was a folder on the Desktop called "temp". Everything went in there first, then got sorted later, and later never arrived. I had four of those folders at one point with names ending in 2.
The thing Dropover changed is the order of decisions. Old way: find the destination, then arrange the windows, then drag. New way: grab the file the moment you see it, decide where it goes when you have decided. Collecting design references all week is where I notice it most, because references arrive one at a time from wherever you happened to be looking.
It also survives space switching. The shelf floats above everything, follows you across desktops and full-screen apps, and does not care that the source window is now gone. That single behaviour removes most of the window-arranging that dragging normally forces on you.
