I purchased the SonoHealth EKGraph because it is cheaper than the Kardia (that is frequently advertised on television), and I needed a way to document the arrhythmias I have been experiencing prior to my upcoming annual physical. The EKGraph is very easy to set up and connected to the smart phone app that records and stores each test with no problems. I love that it does store the test results because the Kardia only retains the most recent test unless you pay them extra for storage. I think it is important for my doctor to see all the test results to get an idea of how often and what types of arrhythmias are showing up, so to me the free storage is a big plus. It is also fascinating to watch the EKGraph operate. You can watch your heartrate, and in my case, it sometimes jumps between rates pretty quickly. While this rate fluctuation is not recorded by the device, I am able to write down the rates I observed along with the date and time of the EKG so that I can share the full set of information with the doctor. I have a lot more peace of mind since I started using the EKGraph because I am discovering that the arrhythmias are mostly rate fluctuations and not "abnormalities." It's amazing to have advanced technology available at such a reasonable price.