RedReader has not disclosed specific data categories it collects, based on its official Play Store privacy label.
Extracted automatically from the developer's own privacy policy text -- not independently verified by Nomatra.
“RedReader accesses the Reddit API. This may occur while the app is in use, or periodically in the background to fetch messages and notifications. Reddit is a third party service and outside the scope of this privacy policy.”
“Google Play provides app developers with various statistics and crash logs. These are collected by Google Play Services, which is not part of RedReader and is outside the scope of this privacy policy.”
“Note: if you have Google Play Services installed on your device, this may collect crash reports from all applications, including RedReader.”
“This policy does not apply to the third party app store(s) from which you obtained RedReader, such as Google Play or F-Droid.”