Hi. Can you explain App compatibility to me from a to z pease. Cause I honestly see don't see app incompatibility on my 6s on iOS 10 and iOS 11 and in iOS 12 now. Still use Mail for emailing, Safari for browsing, Maps for directions, Reminders, Notes, Calendar, Photos, Contacts, and clock to wake me up from my mid-day nap. And they do exactly the same things on any OS. OK, Notes can scan pics or text now, I now have a nifty small program called Measures that I love. But I still use Letgo, Kijiji, eBay, Amazon, Flipboard, News 360, Buzzfeed, Reddit, Google News, SmartNews and some local news apps without any change at all. Maybe I don't get the app compatibility thing cause I'm far from a power user and still view my iPhone as a phone first and foremost. Not a camera or a dignified iPod. Sincerely, explain the thing if I may ask cause I hear a lot about it.