Unlike the resin-encased Apple Watches, this Fitbit wears its silicon on its sleeve, so to speak. Here's what we found:

MediaTek MT3333 GPS SoC

Kingston EMMC04G-M627 4GB flash memory

Fitbit FBT18SW ARM application processor

USI chip (most likely WiFi module)

Cirrus Logic CS47L35 Smart Codec with Low Power Audio DSP

Cirrus Logic CS40L25B boosted haptic driver

NXP SN100T Secure Element