Snapchat and Instagram definitely offer in somewhat similar spaces. All the semi-famous people I follow on instagram have their snapchat username right there in the profile.
People used to share Myspace and Facebook handle as well for a period of time...
Snap used to have an advantage in terms of age group. I'm curious if this is still the case.
Anecdotally I've heard from my partner that Instagram effectively duplicated a core feature of Snapchat to the point she no longer sees the point of Snapchat. But she always saw Snapchat as a side novelty, largely because she used Instagram well before Snapchat.
But I also see this as an age group thing, Snapchat had the image of being popular with high school kids while Instagram had penetrated the university-30yr old category most effectively. So it's hard to say merely as an outside spectator. As well as being geographically limited in my perspective.
I would argue that's a relic from the past. Most Instagram celebrities also had snapchat to post 'raw unedited' updates. Now that Instagram has stories, there probably isn't a strong reason to double post on snapchat as well.
