Given a part of privacy policy text, identify the purpose for which the user information is collected/used. The purpose should be given inside the policy text, answer as 'Not Specified' otherwise

Input: Consider Input: A user's IP address and device IDs is retained for an unspecified duration to fulfill an unspecified purpose.

Output: Not Specified

Input: Consider Input: The site collects your contact information for an additional (non-basic) service or feature. Collection happens on the website, and your data is identifiable.

Output: Additional service/feature

Input: Consider Input: When a change is made to the privacy policy that significantly affects data practices, users are notified when visiting the website. Users can decline the new policy by canceling their account, opting out, or through some other means.
Output: Not Specified