May I ask what's the point? You want a bot to exchange followings just so that you could have more followers even though you don't know who they are, they don't know or care who you are? The fakeness of it all sounds so vapid.
Even he use a bot as explained by naida, it's going to be caught by instagram's algorithm. So basically it's a useless help if he's going to lean it and will do the shortcut method.
Pages that wants to grow followers can easily get advertisers base on the number of their followers and that's why some people think that it's a good idea to have this way of increasing followers but in reality, most followers will be a decoy if they are not organic.