This article is only applicable to https://ASOeShop.com
Please note that we can have only one active campaign for same app at a time i.e we can NOT run multiple campaigns for same app as such but there is a tweak to solve this problem as given below.
If you want to run multiple campaigns for same app then what you can do is while creating campaign choose "Burst" as your delivery type and apply some capping such as 250 installs per day. Do the same with few more campaigns.
Due to burst mode what will happen is the campaign will reach it's daily cap ASAP and go into "Waiting" status then another campaign will become "Active" and after some time that campaign may also reach it's cap then similarly next campaign would become active and so on...