Thanks for clarifying. Since I have one Gen1 device (the Shelly Flood sensor, which was on sale until recently) I would need to keep using the old app anyway for that single device.
The reason I was asking about the potential move to the new app: I have several Gen4 Power Stips. I am using them in WiFi mode, as up to now the Zigbee mode was not working well and offers less capabilities.
I recently updated to the new 2.0.0. Shelly firmware. I noted that I cannot send multiple commands at the same time to the Power Strips anymore, e.g. to switch on three of the four sockets. I need to send those commands in series, otherwise only one is or none are executed.
I was wondering whether that is related to just the new firmware, or to the combination of the old Shelly app for Homey and the new firmware. Do you know whether the new Shelly app handles this better or does it control the Power Strip in the same manner as the old app?