The last speed was my gut feeling of what the ideal option would be, but there’s nothing that tracks it as part of the standard capabilities in Hubitat or SmartThings.
For dashboards that are up all the time, like wall-mounted dashboards, we could track the last speed (in the browser) and use that. But for something like a phone where you occasionally open SharpTools.io, we would have to have some sort of fallback. Maybe check for the
lastSpeed attribute if it’s available otherwise just fallback to a standard default speed.
Edit: If I remember correctly, the official Hubitat Fan Control capability definition declares the supported speeds as
["low","medium-low","medium","medium-high","high","on","off","auto"]. The reality is that most fan drivers don’t implement all the ‘normal’ speeds and I would hazard a guess that even more don’t support special speeds like