Return to Acrobat from another app without having to choose from the 2 dozen open PDFs, just go to the one I was last working with.

The PDFs often have many meaningless names from the scanner, such as SKMC30821051311590.pdf, SKMC30821051706480.pdf, etc.

Running my mouse over the images to pick one can be helpful, but most PDFs are 17x11 format or larger drawings, so a little thumbnail doesn't always help because I lose so much detail due to large format. Also, if they are not my own engineering drawings, I won't recognize them easily anyway.