Senstone may be one of the world's smallest wearables — and perhaps one of the most useful.

The tiny device has one function: to help you keep track of your ideas, to-do lists, and notes while you're on the go.

Senstone records voice memos, uploads them to an app, and transcribes them for you. The device is launching on Kickstarter Tuesday with the goal of raising $50,000, but I got an early version of the Senstone to try out for myself.

Here's how it works.