Different parenting styles with DP ?/not the dad

[Bellagi]

DP is not my children's dad, and we don't live together. He's also ND so im not sure if this is a factor.

He had a very difficult upbringing at times and his parents were very detached. I didn't. He gets on very well with my children but judges me for letting them play on my phone at times or giving them sweets etc. They are happy, well adjusted kids and are very close to me, great at school, lots of friends, your standard kids really.

Just looking for ideas on how to navigate this. I know his parenting style is very textbook/different to mine but I also don't want to rub it in his face that he doesn't have children of his own and that textbook doesn't always work. He's ND.

I would simply tell him to stop commenting on how you raise your DC. It’s that simple. It’s really not his place.
I get that you are ascribing it to him being ND but this does not mean you need to put up with it. I also get that your DC like him and he is saying it to you, not them, but by saying it to you, he is undermining your decisions and judging you.
I had a partner like that (actually DS’s dad) and it’s like you ignore the things like that because most of the relationship is decent. But a decent person does not impose their views like that. A decent person respects your decisions. In my experience, DS’s dad just got more and more controlling and critical if things were not his way. So while you say you are just having a moan, the serious point is that you need to have a line somewhere about what you accept and do not accept.
I also would do the first response to your post now if any man thought he could enter my life and comment on any aspect of it. But I get that is not where you are with this.

He doesn't have a parenting style, as he isn't a parent.