I'm developing a Mac application that monitors a piece of state on your computer and communicates it to a nearby iOS device. Both are using CoreBluetooth to communicate. You can think of the iOS device as a "status sign" for your Mac. I started out by making the Mac the "central" and the iOS device the "peripheral". The Mac tries to keep a persistent BL connection to the iOS device to write a value whenever the state changes. However, I find that the the iOS device often disconnects. I can also see an implementation where the iOS app is the central and subscribes to a characteristic of the Mac peripheral. Here's my question - for those of you with more Core Bluetooth experience, based on my use case, which should be the central and which should be the peripheral?

I have a Mac app acting as as central and an iOS app acting as as peripheral. They are both using Core Bluetooth to communicate. How long can I expect the connection to live? Can connections be long lived? I find that the iOS peripheral disconnects quickly after some inactivity (maybe 10-15 seconds) and I have to keep reconnecting to send more data over. The error I get on disconnection is "Code=6 “The connection has timed out unexpectedly.” (happens all the time on an iOS device running iOS 10 and a newer one running iOS 14). The error message make it sound like this shouldn't happen, but maybe that's how BLE is supposed to work and I shouldn't expect to use it more like a web socket.

In macOS Big Sur, is there a way to remove the rounded corners from the iOS Simulator windows? I'm not looking to change this setting system-wide, just for the simulator. Why? For older simulators like iPhone 8 and older iPads, the rounded corners in the non-bezel windows clip part of what the end user would see. It's small, but it matters in my use case.