I did a very simple experiment on your question:
NSMutableArray *array = [[NSMutableArray alloc] init]; while (1) { [array addObject: [UIPasteboard pasteboardWithUniqueName]]; if (array.count%100000==0) { NSLog(@"%d",array.count); } }
In short, it is limited by the amount of available memory on the device. This means that you get didReceiveMemoryWarning and, in the end, the application allocating memory for the clipboard will crash.
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