Ezt a három szót hogy magyaráznátok meg egy-egy rövid (angol) mondattal?

Satnav - satellite navigation

An electronic navigation system using satellites.

Camcorder - camera recorder

This is basically a video camera and a recorder coupled in a single device.

Smartwatch

Smartwatches can be used to make calls and send texts, making them a convenient alternative to smartphones, with a whole host of convenient features and fitness tracking.