e-Books, consider Kindle. I have Dermatology Secrets and little Fitz on my Android.
Although, I always use Rook to help me answer my bigger consult questions. Online Rook is beautiful on a 4G network running on Android. 🙂 One of my attendings and I dorked around with it on hi iPhone as well, worked just as well.
Expert consult is SOOOOOOOOOOOOO slow at loading, it is painful... I do have Weedon there, which I like to use for virtual slides. Also have a trial version of Bolognia. Otherwise, again, slow. Rook on a computer is very fast at loading. Just note it is in REAL English speak, e.g. "o" here and there where USAmericans don't put them (like me).