I have 3 Lightify bulbs GU10, all in the same bank, off same switch.
Is there a way to group them as one? At the moment I have to use smartapp to do each one, which is ok, but sometimes I want to change the white colour for example to the same and have to do it manually on each bulb.
Osram makes a number of different models, and the answer’s going to be different depending on the exact model that you have. That’s because these bulbs have different “capabilities” in the SmartThings sense: some have capability.colorcontrol and some have capability.colortemperature.
From a practical point of view, there are Osram bulbs that just dim, there are Osram bulbs that dim and change colour temperature (cool white to warm white) and there are Osram bulbs that dim and change colour (red, blue, etc.).
“Dim with me” will work with the ones that just dim, but not with the other two types.
“Trendsetter” can group bulbs together to change colour, but was written for the RGBW bulbs and doesn’t change colour temperature. So you can’t change the white from cool white to warm white as a group with that one, it’s referencing A different capability.
I don’t think anyone has released a smartapp that can handle colour temperature changes for a group of bulbs other than Core itself. So you could do it with core, but that might be more setup work then you want.
I suggest you ask a question in the device thread about the colour temperature changing bulbs. I know quite a few people there took trendsetter and modified it for themselves to add the colour temperature changing ability. I’m sure they’d be glad to share the code or maybe you can get one of them to release a full variation.
Otherwise @sticks18 might have a suggestion, he’s done a lot of work with the colour temperature changing models.