I would suggest another Device, perhaps looking like the “Nuki Button” (also in different designs!) which acts as a Status indicator, paired with the SmartLock.
Something like:
Green light + positive chime (like low and high tone): Code accepted / Smartlock unlocked (and latch opened)
Red light + buzz : Code not accepted, Lock not unlocked
Blue light + positive reversed chime (like high and low tone): SmartLock succesfully locked.
For me it is important to have something while I use my phone for something else.
Another device is I have to pay money for it.
If it’s in the app - it’s for free.
I think the problem is a tiny delay of the notifications. When you set the unlock time to 3 seconds, it sometimes takes longer to get the notification and the door is already closed again.
But I also think that would make it difficult in general to implement such a thing. As long as the phone isn’t connected directly via Bluetooth, there could always be a delay in the communication between SmartLock / Opener and the app, which is longer than the unlock duration.
I agree, that would probably be something rather on the unfeasible side in that case. Some delay between that and the notification is inevitable due to the travel time between the servers.
One solution could be to setup API monitoring on your own server and maybe you could increase the rate (as compared to IFTTT for example), but I’m not sure the effort is worth it only for this consideration.