User Profile

I'm trying to make an app for Apple Watch series 5 that can send a message or iMessage to a number when I click a button in the app. Simlar to how it's done on iOS with the MessageUI framework, but I can't find any similar frameworks for watchOS, and from what I've tried the MessageUI framework isn't supported with the apple watch Messages app. I cannot use WatchConnectivity since that requires an iOS app too, whiles I want this to be a 'standalone' watch app, the message should also pop-up in the Messages app of the apple watch and not on the iPhone. Thank you in advance

The current apple watch series 5 uses photoplethysmography with it's optical heart sensor, right?And it current supports a range of 30 BPM - 120 BPM.However, I would like a way to detect if the user is dead/ there heart is not beating at all, do you believe the current physical makeup of the watch has components capable of this? It does not have to specifically relate to using the heart censors.The ECG would be out of question since the user has to interact with it, so I was focusing mostly on the optical heart sensor.