Only used it a few times. The first time I ran it on two devices simultaneously and when I was done it locked up and wouldn’t unlock even with the hard reset. I had to wait till the battery drained down and start it up again. The next several times it worked without issue on one device. I found it very helpful. I’m a fusser so without the device I’m in and out checking on it. This allowed me to cook inside with knowledge of the meat being cooked. Easy to use and appears to be a good/helpful product.