Privacy Policy

Summary

Rhumb requires no account and has no analytics or trackers. Your data stays on your device or in your own private cloud, with one exception: routing requests, described below.

Location

Location is read from your device to show your position, course over ground (COG), and speed over ground (SOG) on the chart, and to compute your average speed. It is processed on the device. With the optional Background GPS setting (Rhumb Premium), location continues to be read while the app is in the background; your phone shows the standard background-location indicator whenever it does.

Auto-routing requests

When you use auto-routing (Rhumb Premium), the waypoint coordinates you tap are sent over HTTPS to our routing service (api.rhumbapp.com) and its upstream routing engine to compute the route. These requests are used to return your route and for short-term operational logging, such as abuse prevention and debugging. We also keep aggregate request counts (per day, by country and app platform, with response status and timing) to see how much the routing service is used; these counts contain no coordinates and no device or user identifiers. They are not used to build a profile of you and are not sold or shared for advertising.

Markers and backup

Markers you create are stored on your device. You can optionally back them up to your own private cloud (iCloud on iPhone, Google Drive on Android), where we cannot read them. Deleting the app or turning the backup off stops it.

Subscriptions

Purchases are processed by the app store (Apple on iPhone, Google Play on Android). We never see your payment details. We check your subscription entitlement on the device.

App integrity

Requests to our API are authenticated with a device-integrity check (Apple App Attest on iPhone, Play Integrity on Android), which proves the request comes from a genuine copy of the app on a genuine device. No account is created.

Map tiles

Chart tiles load from Rhumb's own servers (tiles.rhumbapp.com, tile-assets.rhumbapp.com) and from OpenSeaMap's tile server. These servers see your IP address and a Rhumb user agent, like any web request.

Changes

We will update this page when the policy changes.

Contact

Questions about this policy: [email protected].