Do it without hesitation, you won't believe the advantages.
Personally I use ForScore. I suggest you check it out, but ForScore seems to be more geared to standard notation. There are others. Some are a little cheaper, but are basically .pdf readers. Onsong like ForScore will transpose and organize your work.
Aside from that there are many great apps for musicians. Metronomes and tuners. One thing I love about iPad is synthesizers that, as a young man, would have cost me tens of thousands of dollars, are now available as soft synths for under $30.00. The are more musically stable and in most cases offer features that the huge, costly originals didn't.
Add to that the news, weather, email, and other internet non-sense and the question of whether to buy becomes moot.
Do it. Stop read this and go buy one.