Postedo - Simple Instagram scheduler that publishes for you
HopperHQ.com - Fully automated Instagram scheduler. Create and schedule your posts online.
Grum - Post on Instagram from your computer!
Buffer - Buffer makes it super easy to share any page you're reading. Keep your Buffer topped up and we automagically share them for you through the day.
InstaGhost - Upload photos directly from your PC to your Instagram account without needing your phone, schedule...
Post There - A smarter way to Auto Post on Instagram without a reminder.