On the surface, it seems a bit of fun, however, having read the terms and conditions as posted by SueDonim, I think there's reason to be wary.
I see myself looking more like my Mum everyday anyway and other family members think I do, too, so I don't need an app to age me another 30 years!
I won't be using it myself as I'm not on Facebook, etc and have no wish to be.
I don't really see how "it's offensive to older people", just something to be wary of, as I say above, given how our data can be exploited.