Seng : iPad I believe like the iPhone has "Notes" applications you can type in. but if you're reading tau geh ji then it comes down to the debate of Music Pad Pro for one purpose or iPad to look cool/trendy and still do the same
There's the guitar tabtoolkit app for Iphone Ipads and Ipod touch, really awesome app, supports PDF, txt and even GUITAR PRO 6! Yes, it even allows you to playback guitar pro 6 stuff with its built in virtual instruments.