Hi, EightString:
Yes, I believe this is all aboveboard as far as copyright goes. And yes, your usage is exactly what I had in mind.
I posted this tip because there have been quite a few long threads lately from people looking for two kinds of help:
1. Help with access and portability of charts/music, especially for gigs.
2. Help with learning tunes.
Of course, we all know how useful the Real Book has been... I have been using it for years. Also, as John points out, the Phillips website is invaluable, especially if you're using it with BB.
I had in mind those uses, like yours, where you don't want a huge load-in of gear, binders, or even laptops, etc. In my case, those gigs which involve only solo piano. I tried the app last night, setting my Droid Incredible on the music stand, and it was surprisingly easy to read (the phone has a great screen, even thought small). I am looking forward to the new tablet computers.....although I see that lots of folks are using laptops and even netbooks.
Also, I am looking forward to using my smartphone to just study charts, when away from a keyboard. I doubt that PG Music will create a BB droid app, but who knows? Everybody seems to be piling on board.

Enjoy,
Daisy