This refers to which smartphone and computer operating systems the fitness tracker device is compatible with. Fitness trackers can only sync and connect with their compatible devices.
iOS: Compatible with iPad, iPod and iPhone.
Android: Compatible with all Android smartphones.
Mac: Compatible with all Macintosh computers.
PC: Compatible with all Windows computers.
Sync type refers to how the fitness tracker device sends the recorded data to your compatible computer or smartphone.
Wireless means that the fitness tracker syncs your data through a connected WiFi network.
Bluetooth means that the fitness tracker has Bluetooth built in and sends your recorded data to a Bluetooth connected device.
Wired means that the fitness tracker device can transfer the recorded data by connecting your device through USB.