Apple seems to rely on long term user training sometimes. I knew that was a send button because I have used previous versions of iOS, it's never even occurred t

Apple seems to rely on long term user training sometimes. I knew that was a send button because I have used previous versions of iOS, it's never even occurred to me that it doesn't look like a button at all. Similarly, I was late to the iOS party, I joined around iOS4-ish, and there were features I discovered completely on accident. Like double clicking the home button on the lock screen to bring up audio controls. Great feature, but I had no idea it was there. People joining in the next few years probably won't know to swipe from the top or bottom until they do it by accident.