Many apps available for recovering deleted messages are safe, as long as they are downloaded from trusted sources such as the Google Play Store or Apple App Store. However, it is important to always check user reviews, the reputation of the app, and read the privacy policies before granting permissions. This way, you can ensure that your personal data and conversations are protected.

Message recovery can vary depending on several factors, such as how long ago the message was deleted, whether the most recent backup contains the message, and the technology used by the app. Some apps are more effective at capturing and storing notifications before messages are deleted, while others rely on backups to recover conversations.

Most message recovery apps are compatible with Android and iOS devices, but there may be some limitations depending on the OS version or WhatsApp itself. 

While most recovery apps are safe, there are some risks to consider. These include potential privacy concerns, such as the app accessing your notifications and messages, and the effectiveness of data recovery. Additionally, apps downloaded from unofficial sources may contain malware. To minimize these risks, always opt for apps with good reviews and downloaded from trusted app stores.