12V Car Battery Tester, TOPDON BT20 Battery Load Tester 100-2000CCA, Cranking&Charging Test via App(NOT for iOS), Record Voltage History, Automotive Battery Analyzer&Checker for Car Truck SUV Boat

This is a terrific unit. Easy to use. Saves test results. Compact and extremely well built. Although the manual refers to a BT20 app, it is not currently available with that name. The developer has provided a work around. Scan the bar code in the manual and it takes you to a YouTube video. You’ll need to download the TestFlight app and the Battery Lab app. Test Flight will provide a code to use to open Battery Lab which is essentially the BT20 so called app. It works very well. I have used for accurate readings on our boat batteries and our two autos with no issues whatsoever. Great tool that is a must for any tool box. As always great to have a good idea of your battery’s state of charge before going to the dealer for service!!

This is going to be a detailed review. The short version is, its a MUST buy!Lets start with the packaging, nice simple box with plenty of information on it. Once you open it up, you find the tester and instructions. The instructions are well written, and in a few different languages.The tester feels nice and solid, if you squeeze it the plastic does not flex or squeak. The clamps are compact but feel solid and they open really wide making it easy to get onto any battery terminal.The tester is simple and advance at the same time. When you hook up the tester to a battery, it will tell you if the battery is low on power right away as you can see in one of my pictures. The first battery was reading at 9.7v and the tester told me right away. On another picture you can see I am testing it on one of my cars that sits a lot. Battery shows 12.1v, but hitting the "TEST" button, it puts a load test and told me it was falling down to 10.6v.The tester is also advance, once you download the app to your phone, you can run a few different test. The load test will graph out the results if the battery drops down a lot. The best part, after every test you can save the results to check out anytime.The last test I tried was the cranking test, right away it told me the battery has low cranking voltage. I suspected this was the case, as it has gotten colder I have noticed the battery struggling a bit, this only confirms what I suspected.My ONLY complaint, I wish they would have put a QR code to download the app, either on the box or instructions. However the instructions does tell you to download the app from either the playstore or Apple app store.Over all this is a must buy for any dyi'er or even a professional mechanic. Also would make a great stocking stuff to any gear head!

I use it all the time in my car and my family's cars. Tells me everything I want to know and it's very easy to use. The only thing I would change is the app name. It's named very strangely so it's easy to forget the name of the app when you're ready to use it. I put a label on it with the app name so I know which app it is.

This product is very sturdy and compact. It works as expected and it’s super user friendly. It’s really everything is needed to test my car battery, and the app works perfect via Bluetooth.I was able to do cranking and charging test while sitting behind the wheel.. Every car owner should have one.Love this tool and the price it’s unbelievably reasonable.

Customer support reached out offering solutions to my problems and defective device so extra stars for them solving the issues.This tester is only useful with a mobile device as the tester itself shows only basic information like the voltage. With the app though, the information provided was not accurate and the SOH (the main reason I bought it) was vague and showed a large range for example SOH: 15%-65%. As well as the battery charge number changing when I disconnected and reconnecting the tester.The bluetooth on the tester also failed on me a number of times. When using the tester on the go roadside, it would not show up on my phone and the app would not recognize it making it useless in the moment.The only pro is that the tester itself is basic and simplified so if you just want to see if a battery has life it can at least do that without a mobile device.