I updated my Mouse to the MX Master 4 and it requires a completely different app to configure than my Craft Keyboard. The Craft Keyboard requires the old Options app and the MX Master 4 requires a new Options+ app and neither are backward compatible. This is SUPER frustrating and I really don't want to have to use two apps to do the same thing, and I won't be waiting for the new app to support the Craft Keyboard, so will be returning the MX Master 4. This new app should never been released before supporting all of the current Logi models. Very disappointed.