I've seen cases that combine a paper notepad with tablet storage, but the Carezza Phone Pocket Folio from Levenger is the first I've seen that has storage for a smart phone.  Carezza leather is buttery soft but strong, and it's available in the black or purple shown in the image (click for a better view).  Inside the folio, you'll find one of Levenger's ruled 90-gsm Freeleaf Notepads with the wide annotation margin that's perfect for showing action points or to-dos.  There are also slots for extra papers, cards, and a pen inside.  The folio is held closed by magnets; the closure “flap” is the smart phone case.
The Gadgeteer , This notepad folio has a place for your smart phone, This notepad folio has a place for your smart phone
