Generally, iOS and VoiceOver are very stable and you should encounter few operational issues. However, there may be times when your device and/or VoiceOver do not seem to be as responsive as usual or in some situations may lock up or freeze while you are using an app.

In this episode of his introductory series, Thomas Domville discusses and demonstrates a few methods that may possibly quickly return things to normal. These include simply restarting your device and a few ways which are believed to clear the memory cache on iOS.