Nokia Asha 501 - What is the difference between Mail for Exchange app and Exchange ActiveSync (Outlook) on Nokia Asha device?

Mail for Exchange client is an application that utilizes Exchange ActiveSync for mail synchronization on Nokia S40 device. In Nokia Asha platform devices Exchange ActiveSync (Outlook) is part of the mail application and supports mail synchronization (text only). Some devices require update to the latest software version to enable Exchange ActiveSync.