I just found this post, which answers a lot of questions regarding which iPad mini to purchase based on the functionality you're looking for: Tablets and phones that work well with DJI GO
The only caveat is that this post is regarding the DJI GO app, not DGI Fly, the latter of which is what the Mavic Mini uses, but I'm assuming it's still applicable.
The only caveat is that this post is regarding the DJI GO app, not DGI Fly, the latter of which is what the Mavic Mini uses, but I'm assuming it's still applicable.