https://believeintherun.com/gps-run-tracking-privacy-policies/

Polar is based in the EU, which has the strictest privacy laws in the world under the General Data Protection Regulation (GDPR). However, this only applies to data subjects within the EU, so if you’re using a device in the United States, you’re not covered by the GDPR (even if you’re a European citizen). The likely reason Joe Rogan received an updated notice agreement was because he was within the EU borders at the time. Companies based within the United States also must comply with GDPR data protection when gathering data from European data subjects.

Does Polar sell your data? No. According to Polar, “the data is used only to offer you the service in question, nothing else. Polar does not disclose, give or sell your data to anyone unless [they] are required to do so pursuant to a mandatory provision of law. [They] may use some of the data in research and development work to improve [their] services, but for such purposes data is cleared from identifiers to the maximum amount possible.”

According to their policy, data is transferred outside your country of origin because they need the data to give you accurate training metrics and recommendations. All their servers are based in Finland, Ireland, and Sweden, so your information only goes to those servers, all under the EU/EEA umbrella. When transferred, “Your data will not be disclosed or given to any third parties; it is still under Polar’s control and under your ownership.

Now, data may be transferred to Polar’s subcontractors that carry out tasks related to Polar, though it doesn’t say who those contractors are or where they are located.

The good news is that you have a lot of rights under their policy, including access to the personal information they have on you, the right to object to the handling of personal data, and the right to refuse profiling and automated decision-making. There are far more rights granted by Polar than other companies.