One action.
Every file.
Add as many PDFs as you like, choose one action, and the same change is applied to all of them. You get one zip at the end. Everything runs in this tab — your files never leave your device.
Add PDFs
Drag & drop several PDFs, or choose them from your device. The same action runs on every one of them.
The action
The same words are stamped on every page of every file.