As someone pretty close to the Fortune 500, I'd like to refute the ego point. Having a quality app - especially with iPads, and especially with higher-spending consumers - is a business necessity. You lose out on a lot of engagement and most of all brand credibility by not having an app.
I think it's hard to put actual numbers to it because it's not a $$$ per app kind of metric - it's a signaling mechanism that a company is still 'with it', and not losing touch. Sort of a 'cool/current' factor, but also a consumer trust that they will be able to operate at the cutting edge if they desire.
It's definitely the native feel. I think for a lot of non-technical people, engaging on a tablet makes them feel like they finally are on top of technology - a sense of control. Perhaps it could be equated to the feeling of mastery when you know a video game quite well.
And also - 'cutting edge' for the average upper class Joes, not cutting edge with technology. A well designed, sleek/sexy - even if simple from a functionality standpoint - app can really get people excited.
I feel a little bit bad about my post, because it is so far from being data-driven, but it's what I have observed from watching 40-60 something SVPs, CXOs, and partners. "Can I do that from my iPad?" is a common question.
Don't feel bad about your post. I like your concept that having an iPad app signals "being with the times".
When I've dealt with Fortune 500 contracts, I never actually met anyone at the company directly. Subcontractor of a subcontractor, all relationships based on trust and prior project results. I think that, ego aside, that maybe it is more about embarrassment and behind-conference-doors shame, if a major company does not have an app, especially if it is an important customer want.
A good trend is that corporations are increasingly investing in the training/risk of building in-house mobile development teams rather than outsourcing. Yes, they run the risk their employees will jump when they have acquired real mobile dev chops - but the truth is there is an intangible benefit to working predictable 9 to 5, 5 day work weeks.
I think it's hard to put actual numbers to it because it's not a $$$ per app kind of metric - it's a signaling mechanism that a company is still 'with it', and not losing touch. Sort of a 'cool/current' factor, but also a consumer trust that they will be able to operate at the cutting edge if they desire.