github.com/openyou/libomron

This looks promising, it lets you collect data from Omron devices. It’s from a quick web search so idk any more about it.

One way this is better than manual logging is that it can run while you sleep. That is, you could have it take your BP once an hour all night or whatever. That’s done in hospitals all the time. It’s uncomfortable so I wouldn’t do it routinely, but it might be worthwhile if you suspect something might be up. Obviously, discuss it with your Dr too.