Can an iPad Air be used for digital artwork? If so what programs would you use? And what stylus?
Yes. Tayasui Sketches. Finger.
It depends on your definition of digital artwork, and I've never tried anything detailed on iPad, but the above are fine for quick sketches. The paid version of Tayasui has more facilities including an exceptional wet ink simulation. Artrage is also easy to use though it's premium only.