Twitterfall - Twitterfall is an excellent choice if you want something basic, free and without much branding.

RecurPost - RecurPost is a social media scheduler with repeating schedules. It allows you to schedule content on multiple social accounts from a single dashboard.

Flightly - The must have mobile app for anyone advertising on Twitter.

Elevate - Elevate is an award-winning brain training tool designed to build communication and analytical skills.

Fenice - Read writing from Fenice for Windows on Medium. Fenice (fka Project Blue Dog) is a full-featured Twitter app for Windows designed to offer the best Twitter experience to every user (pro or casual ones).

Later - Schedule and manage your Instagram posts