If you’re into reloading, you know about chronographs. Odds are you might have a Shooting Chrony. I myself happen to own a Shooting Chrony Beta Master. These are pretty well made devices, and Shooting Chrony has a no nonsense replacement policy.
The only way to interact with the device is via a proprietary 9-pin-female RS-232 cable, like an old modem. Now, this techique was all the rage circa 1994 when dial-up internet was king and everybody had PC’s with two or more serial ports. This is really sub-par when you want to try and connect your smartphone to a Shooting Chrony (yes, this is possible, but more on this later).