Amazon is warning users not to update the iOS Kindle app, as the most recent release of the software appears to be deleting entire book libraries and saved settings from iOS devices, according to customer reviews. Amazon notes that version 3.6.1 of the app has a known issue: “If you are an existing Kindle for iOS user, we recommend you do not install this update at this time.”

Update: Amazon has released a new version of the iOS Kindle app, 3.6.2, which features a “fix for registration issue” and “various bug fixes and security fixes.”