I've been looking for something similar for my PDN. I was able to successfully install and test the following five apps. Unfortunately, none really does what you're asking for.Semi-solution:
Note Everything Free You can create text-based notes or handwritten ones. The text part is fine. The handwriting option only runs in a 300x400 subsection of the display--it doesn't scale to fill the PDN screen. There's a significant lag between input stroke and rendered stroke, but actually the lag on this app was the shortest of the three drawing apps I tried.
http://db.tt/atoyCbIf you just want text-based apps:
Evernote seemed to work fine for me. Trying to create an image note triggered a crash--it seems to demand a camera on the device, regardless of whether you have images on an SD card. Same with audio recording obviously. But for short text notes it was the best/easiest/most legible interface.
http://db.tt/c8mNzUIf you really really want a drawing/handwriting notepad solution:
Draw and Share Definitely works, but it's cursed by an awful lag time between input and rendering. Only useful if you're really patient and a slow writer.
http://slideme.org/mobileapp/download/b6846020-55bc-102d-a134-12313a00d126.apkI'd pass on these:
AK NotepadText notes only. Sadly, unreadable on the PDN. The fonts display at a ridiculously tiny size even on the largest font setting.
AndroPaint LiteFull screen drawing, but lag was so bad that it made it unusable. Frequently "forgot" my input strokes if I didn't pause and wait after every movement.