I don't have Home Assistant, but I do have Hubitat. So my question is that is there easy way to use this custom app made for Home Assistant directly in Hubitat as such? If not, what would be the easisest process of doing so?
Naturally if there's already available same kind of custom app for Hubitat I would be interested.
Not directly. You would have to install Home Assistant somewhere else, and install the app under HA. And then use Home Assistant Device Bridge to import the device(s) into Hubitat.
Without having looked at the home assistant app, another option would be to develop an equivalent app for hubitat. That may or may not be something you would be prepared to do, but there may be others here who may be interested.
It’s going to cost something to someone, one way or another .
The fact that there’s a home assistant integration means it’s technically possible for this device to integrate with another outside system, like Hubitat.
So it will cost a developer’s time to create that integration. That developer could be you, another member of the community here, or a Hubitat staffer (theoretically, I’m not suggesting there is an official integration option here).
Or it’s possible to link Hubitat and home assistant thanks to the work already done by Hubitat community developers (for free). But the associated cost there is the device needed to run Home Assistant.