In-app messaging can be an effective way to communicate with users, but if not done correctly, it can lead to user overwhelm and frustration. To avoid this, consider the context, audience, frequency, and metrics of your in-app messages. Ensure that each message is relevant and valuable to the user, and personalize them based on user behavior and preferences. Use unobtrusive messaging styles, such as banners or customizable widgets, and make it easy for users to dismiss or snooze messages. Finally, control the frequency of your messages by setting rate limits and adjusting them based on user behavior. By following these best practices, you can create in-app messages that enhance user experience rather than detract from it.