Free software on your phone or tablet lets you scan, create, edit, annotate and even sign digitized documents on the go. By J. D. Biersdorfer I write the monthly Tech Tip column, which is devoted to ...

There's no file format quite like a PDF when it comes to keeping your documents neat, locked-down, and exactly as you intended. Once you send one off, nothing shifts, stretches, or jumps to the wrong ...