Glow App Alternative: Trackers Without Data Monetization

Glow is cloud-based with no documented on-device storage architecture. Here's what that means for your reproductive health data and what to use instead.

Glow is a cloud-based period tracker with no documented privacy architecture. Your reproductive health data is stored on Glow's servers. Floriva keeps core records on your device and has no readable central cycle database to sell or hand over.

What Glow Doesn't Document

Glow is a period and fertility tracker that has been available since 2013. It offers cycle tracking, fertility prediction, pregnancy tracking, and community features. The app has a substantial user base and broad feature coverage.

What Glow does not offer is a documented privacy-first architecture. The app is cloud-based. Its privacy policy does not clearly commit to avoiding data sales to third parties. There is no on-device storage model and no published commitment to zero-knowledge design.

Documented Privacy Failures

Glow has a specific enforcement and breach history. In September 2020, Glow settled with the California Attorney General for $250,000. Investigators found the "Partner Connect" feature automatically granted data access to anyone who sent a linking request, without the recipient's confirmation. This exposed intimate health data including miscarriage and abortion history to unauthorized parties. Consumer Reports originally discovered the vulnerability in July 2016. The gap between discovery and settlement was four years.

In October 2024, security researcher Ovi Liber discovered an API bug exposing personal data of approximately 25 million Glow users, including names, age groups, location data, and user-uploaded images.

Mozilla's Privacy Not Included review found Glow's privacy claims were "easily shown to be false" regarding data sharing practices. The pattern is consistent: privacy claims that do not hold up under independent review.

The Architecture Gap

Period tracker data is sensitive. It includes cycle dates, fertility status, pregnancy information, and symptom logs that can reveal health conditions. When this data is stored on a company's servers, three risks apply regardless of the company's intentions: the company can change its privacy policy, a legal process can compel data disclosure, and a security breach can expose the data.

Glow's cloud architecture means all three risks apply. The company has not published technical documentation that would indicate mitigation of any of them.

How Floriva Compares

Floriva keeps core records on your device. There is no readable central cycle database to sell, breach, or produce from our systems. If sync is on, Floriva only receives end-to-end encrypted data that we cannot read. For users who want Glow's fertility and cycle tracking features without accepting readable cloud storage, Floriva is the architectural alternative.

Strengths and trade-offs

Glow

Pros

Detailed fertility tracking
Partner and community features
iOS and Android

Cons

No documented privacy architecture
$250K California AG settlement for unauthorized data sharing via Partner Connect
25 million users' data exposed via API bug (October 2024)
Mozilla: privacy claims 'easily shown to be false'
Cloud-based data storage
Account required
Data monetization business model

Quick answers to the obvious questions.

Is Glow safe for period tracking?

Glow is widely used but is cloud-based with no documented on-device privacy architecture. Your period data stored in Glow is accessible to the company, their business partners, and law enforcement with a valid subpoena. For users in states with abortion restrictions, this carries real legal risk.

What was the Glow California AG settlement about?

In September 2020, Glow settled with the California Attorney General for $250,000. Investigators found the Partner Connect feature automatically granted data access to anyone who sent a linking request, without the recipient's confirmation. This exposed intimate health data including miscarriage and abortion history to unauthorized parties. Consumer Reports originally discovered the vulnerability in July 2016. The settlement came four years later.

Was Glow's user data exposed in a breach?

In October 2024, security researcher Ovi Liber discovered an API bug that exposed personal data of approximately 25 million Glow users, including names, age groups, location data, and user-uploaded images. Separately, Mozilla's Privacy Not Included review found Glow's privacy claims were 'easily shown to be false' regarding data sharing practices.

Questions people ask before they switch.

Is Glow app safe?

Glow is a functional period tracker. From a data privacy standpoint, it is cloud-based with no documented on-device storage architecture. Your reproductive health data is stored on Glow's servers and is accessible to law enforcement via subpoena.

Does Glow sell your data?

Glow's privacy policy does not clearly commit against selling or sharing data with third parties. Unlike apps with documented data-selling enforcement history, Glow has not been subject to FTC enforcement, but it also lacks the transparent privacy architecture of on-device-only apps.

What is a private alternative to Glow?

For users who want Glow's fertility tracking features with stronger privacy, Floriva (on-device storage, no account required) and Natural Cycles (FDA-cleared fertility tracking, though cloud-based) are the main alternatives.