Followerwonk - Followerwonk by Moz is a Twitter analytics tool to help companies better understand their Twitter followers.
Iconosquare - Schedule now. We'll post on Instagram for you later!
burrrd. - A beautiful UI that provides you detailed twitter analytics.
Later - Schedule and manage your Instagram posts
Twitter Ads - Twitter offers targeted ad placement on their ad platform.
Storyheap - Manage your SnapChat and Instagram stories.