By David Goldman, Heather Kelly and Jose Pagliery @CNNMoney December 18, 2014: 4:10 PM ET
Dash, $69
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Dash's tiny sensor connects to any car model made in 1996 or after -- it plugs in just underneath your steering wheel. It connects to your phone via Bluetooth, and Dash provides useful driving information: What your check engine light means, how you're driving, and how much gas you're using. It'll even tell you where the cheapest gas is and how much you should pay for repairs.
