Yes. While we can’t speak for every app, pass­word managers from trust­worthy producers are safe. A pass­word manager is especially useful for storing secure pass­words that you have created with a generator. On top of that, a good manager comes with a secure pass­word generator of its own. A pass­word manager typically stores the pass­words on your device. They can’t be stolen online. Because of strong encryption, it’s practically impossible to break into a pass­word vault without the right pass­word or finger­print. Also, an attacker would first have to get to your device.