The icon that ships with the module

Until you upload your own, the app uses a stack of rack units with one lit status light. It is deliberately generic, and it is a real icon rather than a coloured square, so an install with nothing configured still looks finished on a home screen. Four files ship: the standard 192 and 512, a maskable 512 with the mark pulled inside the safe area that Android crops to, and an Apple touch icon. There is a vector source alongside them if you want the same shape in your own colours. Upload your own 192 and 512 on this screen and yours are used everywhere, including for the maskable slot, since only you know whether your artwork survives being cropped to a circle.