Apps · Drive, safety and recovery
Can I lose an app by moving it with Storage Studio?
Short answer: A failed or interrupted move won't lose the app — the original is kept until the copy is verified. The bigger risk is the drive itself failing later, so keep it backed up.
A failed move won't lose your app: the original is kept until the copy is verified, and interrupted moves resume or roll back on their own. The real risks are afterwards — a moved app depends on the drive, so if the drive is lost or fails, the app on it goes too.
That's easy to recover from — reinstall the app, and its settings are still on your Mac — but it's why a backup of your external drive is wise. See backups.