Bests & Worsts Reviews from Amazon

So my engine light was on for a few days, and I made an appointment with my mechanic. I decided to get this to see if I could fix it myself. I got it the night before my appointment and it took me all of 5 minutes to download the app and plug it in. Very easy, I have a Jeep and the port was right under the dash. So it came up as a thermostat that was going bad. I kept my appointment with my mechanic because I knew I couldn't fix that myself, but I didn't say a word about what could be wrong. They diagnosed the same thing so now I know it really works!