PDF Expert has a collection of stamps you can add to your PDF files. Moreover, you can create your own stamps with texts or images.
For the text stamp, you can type any text you like. To include the current date or time to your stamp, enable the Date or Time toggle. PDF Expert automatically updates the date and time on your stamps.
For the image stamp, you can select a picture from Photos.
Note: The stamp you create is available in the Custom tab of the Stamps menu.
Once you added a stamp, drag the corner of the stamp to resize it. Later on, click the stamp first, then drag the corner of the stamp.
To resize the stamp, tap it and drag its corner.
Right-click a stamp and choose one of the actions: