Are your assets safe on Kraken??

I was about to make another deposit through Kraken app, as I was prompted to update the app.
I followed to an App Store to try and make sure it’s the right App and all and before updating I started reading this App reviews.
To be honest I am a little concerned now, because there people saying in the reviews that their accounts were closed without any explanation for security reasons.

Could you please tell me what you think about it??