We are using iPads where in at and it's great. We got approval using a leg strap which is not so great but it got us approval. We also have 4G which is helpful. On wi-if airplanes is a great tool to communicate with company, although, a cars probably takes care of that for you.

We also run w + b on it with a real nice little app and all company documents are on it. Really one of the best overall tools we have in the airplane. Certification takes awhile though. I think you'll like it when/if you get them. 121 is probably a little more stringent on getting them approved.