Change size for printing

I have the latest iOS version of ArtRage (ver. 2.3)

Is there a way to enlarge the image I did on my iPad before I send it for printing, or are large formats exclusive to the PC/MAC?

There's no way to resize the painting in the iOS version of ArtRage.

When you create a new painting, you can set a canvas size up to 2048 x 2048 pixels, or 4096 x 4096 pixels if you're using an iPad Pro.
When creating a painting on the iPad version, recording can also be turned on, then the script file can be played back on your PC or Mac at a larger size if you have the full version of ArtRage on your computer.