Thank you for your post.
A Container field allows you to capture a signature on an iOS device. If you tap a blank Container field in FileMaker Go, you get the option to "Choose From Library" or "Get Signature". Once you select "Get Signature" and enter a Signature, tap "Accept", and the signature will be stored in the Container field. You can also use this for hand-written notes or to display a hand written document. Just make sure it is fully visible within the Container field and positioned appropriately on the Layout. Then, when you tap Print -> PDF, everything on the Layout will be included.
Let me know if you need additional clarification.