Instagram group - how to manage?

Hello guys!
I'd like to know about how to manage an Instagram group with some members where a member post about the other member.

I know I can do it by hand. For example: 
- Member 1 please share the last pic from member 2.
- Member 2 please share the last pic from member 1.

But I do not have time to monitor if everyone is doing what they need to do.
And if not, I will problems like:
- hey, member 2 has not post my pic yet.

Do you know if there is a software that I can use for that?


In this way I can have a better way to create categories (less than 10k, less than 20k, less than 40k...).

Do you have experience with this?


My niche: fitness

Tks!

Actually, I don't have many expriences in using Instagram. Because I often use Facebook than Instagram and it can easily control other actions. I am developing my website and spreading it to everyone. Maybe it has a few bugs or is not attractive enough, so you can go to the griper (dot) net website to give some ideas. Hope to get feedback and suggestions from you