The app used to synchronize data to an iOS-based mobile device is iTunes.
iTunes is a media player, media library, and mobile device management application developed by Apple. It is used to manage the synchronization of music, videos, photos, and other digital content between a computer and an iOS-based mobile device, such as an iPhone, iPad or iPod Touch. iTunes also provides access to the Apple App Store, where users can download and install apps on their mobile devices.
Auto Sync, MIME, and SMTP are not apps used for synchronizing data to an iOS-based mobile device. Auto Sync refers to a feature that automatically synchronizes data between different devices or applications. MIME and SMTP are protocols used for sending and receiving email.