The iPhone gives you the ability to record conversations, a feature which can be quite useful when you want to take notes or reminders.
Note that: The iPhone doesn't allow you can not record your phone calls. The reason is that because Apple prohibits interaction between running apps. It is therefore impossible for an application to record a conversation when the "Phone" module is active. The only way to overcome this limitation is to jailbreak the iPhone. The fact that this operation may damage your device and you will lose the warranty.
We can still save record calls made with the iPhone via an external service that records calls via its server. Applications "ipadio " and "Google Voice" provides such features.