Below is an instruction that describes a task, paired with an input that provides further context. Write a response that appropriately completes the request.

### Instruction:
Summarize the essential features of a certain product.

### Input:
Product Name: FitBit

### Response:
FitBit is an activity tracker which helps users monitor their health and fitness. It measures steps taken, distance traveled, sleep pattern, and heart rate. It also syncs with a companion mobile app to give users detailed analysis and insights. Additionally, FitBit supports goal setting, provides reminders, and offers motivational challenges to keep users motivated.