Good point about the 'Dock' word - but it is, (for want of a better description) a 'guiding' word - people know straight away what it's about
+1, and branding is everything, especially in a commercial product. Though I suppose there are other words that might convey the same thing, especially since the 'Dock' doesn't actually dock to anything, unlike other docks out there.
Maybe launcher, i.e. Circle Launcher?
Looking at synonyms for launch- Cast is one that it puts forth. So App Caster? Or maybe Activator would be a word to use since it's also a synonym.