Edit: To sum up my question, what is the established back gesture for iOS games (when no pause button exists)?
I have a block puzzle game, square grid, and some levels fill up the whole screen with them. In Android this is no problem because there's a hardware back button. iOS devices, however, have no such thing.
I need some kind of back button to get to the menu, where you can restart, undo, select other levels, go to options page, etc.
I looked at iOS game demos on youtube. All I found was many of them have a pause button in some corner, but this is not a great solution in my case. I could not find a demo illustrating some kind of back gesture, like swiping from the left edge towards the right? Most demos are direct screen captures instead of showing a user and their hands, so I could not confirm this.
I figure most iOS games have adopted some kind of standard practice for this. What is it?
EDIT: I found this article about iOS 7 doing a left-right swipe to go back one page, apparently for safari. This was kinda my first though, because surely there is a back gesture for the back button of web pages? I don't know if this same gesture is standard practice in iOS games, but I put it here because it's my first guess.