In an automated fashion? No. But it's definitely possible.
If you want a border around the entire image:
Add a blank layer by tapping the "+" in the lower right corner of the workspace. Tap, "Empty Layer," Tap, "Done."
Select the entire image by tapping the icon in the upper left, fourth from the leftmost (this icon represents selection settings) > "Select All." Tap the icon again > "Transform."
Tap, hold and drag one of the corner handles and release. Tap anywhere within the selection and move slightly towards the center until the selection "snaps" to the center; release. Tap the checkmark.
Next, tap the icon from the first step once more (the selection settings icon) > "Inverse."
Tap the ampersand icon in the upper right, second from the right > "Fill & Stroke." Fill with a color that contrasts with your text. Tap the checkmark.
You'd then add your text.