Google's Mobile Service: AI Listens In and Improves Audio

Google is routing calls from its US mobile service, Fi Wireless, through its servers. There, an artificial intelligence manipulates the audio. The goal is to suppress background noise and amplify spoken words. Google activated this for all Fi customers with iPhones or Android phones (from Android R) according to a circular dated December 22, 2025. Many questions remain open.

While Fi customers can disable the feature in the Fi app, and Android phones display a notification during the call, it is unclear whether the conversations will continue to be processed by the AI servers without audible influence or not. Similarly, it is unclear what happens if one call participant has deactivated the feature while another has not. Google's Privacy Policy contains no relevant information about the new service feature, only stating generally that Google may collect and use “voice and sound data” for numerous purposes.

heise online has asked Google for information three times but received no response. Therefore, it remains unclear whether international connections are also processed, how long the data is stored, and what else Google does with it.

It is not out of the question that the AI attempts to determine the identity of participants through voice recognition. It is conceivable that the AI listens to the content of conversations. Such findings could be used for tailoring advertisements or, if indications of an emergency or potential crime are detected, for information to authorities. There are no indications of such measures available to the editorial team.

Legal New Territory

The storage duration is not only practically relevant because it could enable authorities to retroactively eavesdrop, but also legally, as US authorities can access data stored for longer than 180 days much more easily. Even without storage, the legal situation is unclear: Is processing by AI considered eavesdropping? If so, it depends on the US state whether the consent of one call participant is sufficient or if all must have consented. And since Google activates AI processing automatically and only offers opt-out, the company could get into legal trouble.

Furthermore, US data protection generally focuses on the expectations of data subjects regarding privacy. The protection of the Fourth Amendment of the US Constitution against government surveillance does not apply, according to prevailing legal opinion, if the data subject has voluntarily disclosed their data to a third party. Here, Google is a telecommunications provider for whose core functions special regulations apply, but the conversations are now also routed through systems that are not necessary for the call connection.

This looks like a data protection time bomb that deserves more than an opt-out hidden in an app with unclear effects. Google's legal department has surely thought about this; however, the data giant remains silent.

Project Fi

Google has been operating Fi Wireless (formerly Google Fi, previously Project Fi) for almost eleven years. The company acts as a virtual mobile operator (MVNO). The service uses multiple US mobile networks, which otherwise compete, for better network coverage.

The billing is flexible, as the service can be paused at any time, which stops the calculation of monthly fees without losing the phone number. Speaking of billing, Fi mobile bills are now even longer by one page because there is now an AI-generated summary of the bill.

(ds)