Application can receive SDL_APP_WILLENTERBACKGROUND, SDL_APP_DIDENTERBACKGROUND, SDL_APP_WILLENTERFOREGROUND and SDL_APP_DIDENTERFOREGROUND, but cannot receive SDL_APP_TERMINATING.
I deep into SDL code. Once termiations app on iPhone device, applicationWillTerminate in SDL_uikitappdelegate.m is called, so execute SDL_SendAppEvent(SDL_APP_TERMINATING). But application cannot this notification!