Whistle Switch

Whistle says that the device tracks "pet’s health, fitness, gps location, and so much more." This privacy policy only applies to information collected by the app ("Whistle: Smart Pet Tracker") and other places your info is collected, like websites and social media. The data practices related to the device itself are unknown.

Per NYTimes article from September 2021, Whistle told journalists that they do not share customer or location data from the Whistle Go tracker or app. However, according to the Mars (parent company) privacy policy, Mars does collect and share data with third parties for targeted ads. This privacy policy only covers what the app ("Whistle: Smart Pet Tracker") collects, so the data practicies related to the device itself are unknown.

Mars says they can "get protected classification characteristics directly from you or from third parties, such as data brokers or social media platforms." That they get "geolocation data directly from you, indirectly from you (e.g., if you allow location services), and/or from third parties like social media platforms." Third-party service and advertising partners may also collect information automatically. In the app, they collect data on users such as age, gender, hobby or activities, taste or preferences. The app also collects data on pets such as your pet’s species, breed, birthday, or treatment history – which is not considered Personal Data. Mars may use demographic and preference information for advertising to target users for whom they are most relevant. Finally, Mars says, “We may sell anonymized data to third parties, and we may share anonymized or non-personally identifying information as described above. We may combine anonymized or de-identified information with other anonymized or de-identified information from other sources. We also may share aggregated and anonymized information with third parties, including for example advisors, advertisers, and investors, for general business analysis.”

You can ask to access or delete your data, collected through the app. But Mars will respond to any rights request in accordance with local legal regulations.
There is no mentioned way to delete data on your pet, as there is no privacy policy related to the device.

Whistle says that the device tracks "pet’s health, fitness, gps location, and so much more." There is no device-specific privacy policy, so we are unable to find out which of these data is transferred to the server, how it is shared/sold, and how it can be deleted.