I would like to define tasks using NSDictionary, which I'd like to save in a plist file (I didn't have much luck with Core Data so far), but got stuck at two points: -- When using initWithObjectsAndKeys: I can change the data type to number or boolean, using NSDate's numberWithInt: and numberWithBool: methods, respectively. I can't seem to find the method to change the type to date though. I couldn't find anything like that in the documentation. -- The second problem I ran into was with the nested arrays. How can I add them to the dictionary? I have uploaded a picture to here of what I am trying to achieve. Thank you in advance!