Is the Castle app safe and legal?

It is an illegal app so it has security concerns. It does not give too much security to the user’s device.
It is not a proper legal app. It is a third-party app that does not give a 100% security guarantee.
Every platform has some rules and regulations. Similarly, the Google Play Store has also regulations. It has been made against the rules of the Google Play Store. Therefore, there is no chance of the safety of users’ data. If the user also does anything against the rules, it will end in the suspension of the user account.
Google also has some terms that every application should follow. But the castle TV app does not sign with Google terms. It has not obeyed Google’s terms and policies. Therefore, in case of any mistake or negligence, google directly banned the user data and account.
The castle movie app is not based on any concerned author. It is just a third-party app without any written policies. It has no authorized terms and regulations. That makes it more unsafe for users to believe in the security of the Castel app.
It does not have permanent authors. There are no names of the authors of the castle apk. Managers handle it. No one takes responsibility completely. Therefore, it has less chance of customer support service in case of any doubt or warning.

Tips and tricks to be secure from all the threats:

You can protect your data by following the terms:

You should not break any rule given in the app.
You have to follow the terms given by Google also.
You have to download the app from a valid website.
You should check the version of the castle apk carefully. Keep it in your mind. You have to install the latest version. The old version may have some issues.
You should not give access to your data to any third-party app.
You should be careful about opening any ad.; sometimes ads cause hacking.
Always connect a stable internet with your device while using the Castle app.
You have to check the version that is appropriate for your device; sometimes, a version is not compatible with a device.
Always allow unknown sources from your device. Others will not allow you to install any app.
Do not open unnecessary and strange websites while using the Castle mod apk. It will lead you to give access to your data.
Keep updating your castle apk. It will let you install new features in the app, which is a good thing.
Always keep on your notifications that will keep you updated with the upcoming new version. Or any change related to the app.