Apps
There is an app store on the device. That is where functionality comes from.
The controller ships with a store on the device. You browse it, install what the installation needs, and the app is there after a reboot and after a firmware update.
An app is a unit of function, not a plugin that patches the core. Removing one takes its values off the platform; it does not leave the controller in a different state.
What is in it
Energy strategy, PV forecast, EV and heat-pump extensions, evcc, Node-RED, Home Assistant, EEBUS, Tailscale, an AI assistant and a sandbox — eleven in total. The catalogue with a line on each is on Apps.
The install flow itself: where the store lives in the UI, what an install looks like, and what happens to installed apps across a firmware update. Needs screenshots.