It's my opinion the IOS s/w development team at DJI is more proficient than the Android s/w team. This has been proven over the years with new features appearing on IOS way before Android supports the same feature. The other reason I prefer IOS is because DJI s/w developers have a concise platform to develop for and test on, one manufacturer (Apple), and fewer models to test. With Android there are many manufacturers, and each manufacturer is using a different CPU architecture, making compatibility more sketchy to test and validate, way more risk involved, and much more testing needed to equal the quality steps needed for IOS. And we all know that DJI has a history of letting their customers do beta testing for them, so I vote IOS to fly DJI drones, even though I use Android for my personal phone.
If you can afford it, I recommend an iPad Mini 5. I've used an iPad
Air2 with cellular for years, it worked well. About a year ago I bought the new regular ipad without cellular, and I'm happy with it, works well just like my iPad
Air2. However had the new iPad Mini 5 been released, I would have bought that, because the physical size fits into the Mavic controllers with no adapter. I used a Mini2 with my MP for a year. It's really convenient to have the Mini fit the controller clips, eliminating setting up an adapter to hold my larger iPad every time I fly my M2Z, not to mention the added cost of the clip adapter and having to tote it around in the backpack, taking up space. With my MP I would leave the iPad Mini installed into the MP RC clips, and it would fit into my backpack, connected, ready to use. This made it convenient to LAUNCH FAST when I arrive my flight spot. I simply unfolded the MP, turned it on, turned on the RC, wait for GPS sat-lock, and take off. FAST and EASY. I like that.