What is SIM-based geo verification, and how is it different from IP or GPS checks?

IP geolocation maps the visitor's IP address to a place using commercial databases. It is the most common signal on the web, and the easiest to fake with a VPN. For that reason many services flag VPN and datacenter ranges and respond differently to them, sometimes with a block, sometimes with a default market.

GPS and other device location services report where the phone says it is. Browsers only share that location after the user grants permission, so most websites never use it for pricing or content. It is also simple to spoof on a test device, which makes it weak evidence on its own.

SIM and carrier signals come from the mobile subscription itself: the carrier's network assigns the IP address, and apps can read the SIM's country and carrier codes. A real local SIM on its own carrier network produces the combination of signals that a local mobile user produces, without an intermediary that can be detected.

The goal is to compare what a market is supposed to see with what it actually sees. The useful fields are content, price, currency, call-to-action, language, availability of products or features, and any restriction message. Screenshots tie each field to the page it came from.

The network context must always be declared with the result: whether the phone was on the carrier's mobile data, on Wi-Fi or roaming. A result that hides its context cannot be trusted, because the same page can legitimately differ between those paths.

A check reports what was observed, not why. If a product is unavailable in a market, the reason may be licensing, regulation, a pricing rule or a configuration error. The observation is the starting point for that investigation, not its answer.

You declare the context you expect, such as language, currency, price and availability, and the targets to check: 2 on the Founder plan and 4 on Standard. A physical Android phone with a real local SIM loads each target and records what it observes, with screenshots and the network context stated in every result.

Each check compares your expected context against what one real local SIM in Latin America observes; it does not place two countries side by side. The SIM country is stated at checkout, before payment.

Every run is signed with Ed25519 and can be verified publicly. Screenshots are kept 60 days on Founder and 90 days on Standard. The system measured 1,281 qualified backtests at 99.05% autonomy (2026-09-15), a figure about the system's own reliability under injected faults, not about any site.