Apple

I've made a really simple iOS app. It's a label that shows the current count--which starts at 0--plus buttons to add 1, subtract 1, or reset the count. The app works fine with VoiceOver, but when I tap the Increment or Decrement buttons, VoiceOver just says the button name. What I'd like to do is have the label post some kind of notification, so VoiceOver will speak the new count even though focus remains on the button. I know I could speak a string with VoiceOver directly, but I thought I'd read something about a way to have VO speak changes to certain elements on the screen? Am I thinking of something else? Thanks, and I hope I've made sense. :)