title: Save NSMutableArray to load when reopenning iphone app
body: <p>I have a NSMutableArray, each item in this array is different class. In each class has many field such as CPPlot, identifier,... (I am using CorePlot to develop a stock application). Now I would like to store this NSMutableArray to load when user reopen application, this will load all the chart they used before.</p>
  
  <p>I try to figure out how to do that in Stackoverflow. And I found out there were 2 solutions:</p>
  
  <p>NSUserDefaults</p>
  
  <p>SQLite database</p>
  
  <ol>
  <li><p>In NSUserDefaults, when I want to store NSMutableArray, I must implement with NSKeyedArchiver to archive and unarchive array object, also do NSCoding protocol for each item in array object. But I can not do this solution because in each item, it has some fields from CorePlot library, so that I can not use NSCoding to these fields.</p></li>
  <li><p>SQLite database, I can not use this solution because each item in array object is different class.</p></li>
  </ol>
  
  <p>I would like to ask if any other solution to solve this problem?</p>
  
  <p>I hope my words are clear enough to understand.</p>
  
  <p>Thanks</p>