Honestly, I have never seen advertisements for this app and had never heard of it before you mentioned it. It might be because I'm an expectant mother and not a full-on mom in search of friends yet. To say the least, it has me intrigued.
I set up an account to try it out and just see what it looks like and it seems mostly like a Facebook mom group. There are a lot of odd questions and some complaints about familial issues. There are a few random posts, like a post with a picture of a foot and asking if they could become a foot model and how to sell photos of your feet for money. Not very mom related, but whatever is best for them I guess.
My state is somewhat small and my area is not very popular with the app, so there was only one local group to join and no local mommas. I guess how useful it would be would depend on if the area you live in has very many moms that participate.