Private by design. Plain about the network.

About this policy

This policy covers the StockSim website and mobile app. StockSim is an educational practice-investing product. It does not connect to a bank or brokerage, accept real deposits, execute real trades, or require a StockSim account.

The StockSim website

This website has no analytics, ads, tracking pixels, account, contact form, cookie, or browser storage. It does not run JavaScript or request third-party fonts, images, or scripts. An email link opens the visitor’s own mail app; the website does not receive the message itself.

Vercel hosts this website. Like an ordinary web host, Vercel can process request information needed to deliver and protect the site, such as an IP address, request time, requested page, browser information, and diagnostic or security logs. StockSim does not add website analytics to those hosting functions.

What the mobile app keeps on the device

Practice cash, deposits, withdrawals, holdings, trade history, portfolio history, research notes, watch prices, completed lessons, and appearance settings are stored in local app storage. StockSim does not send those records to its market service and does not offer cloud sync.

Removing the app or clearing its storage can remove local records. Device backups are controlled by the operating system and device owner.

What happens when the app requests market information

The app sends a company or ticker search term, or an investment identifier and requested date window, to the StockSim market service hosted by Vercel. The service receives ordinary network information such as the device IP address, request time, and requested resource. Vercel may process request and runtime logs as part of hosting and protecting that service.

The production service asks Massive for U.S. stock and ETF listings, dated prices, price history, stock splits, and supported cash dividends. Massive sees a request from the StockSim service, rather than a direct request from the learner’s device. The request does not include portfolio balances, share quantities, trades, notes, lesson progress, or settings.

How market responses are cached

StockSim temporarily caches validated market responses to reduce repeated requests. A company search can contain the entered term and matching listing information. Service memory can retain that response for up to 24 hours. The shared Upstash cache uses a one-way hash of a credential-free Massive request URL as its key and stores the corresponding validated response for no more than 24 hours. Price-bar and corporate-action responses use the same or shorter application-controlled periods.

Responses can also use standard HTTP caching for the period stated by the service. Vercel, Massive, and Upstash may process their own operational, security, and diagnostic records under their respective service practices.

Background price refresh

When a connected portfolio holds investments, StockSim can ask the device operating system to run a best-effort daily refresh. The operating system decides whether and when it runs. The request identifies the investments that need prices; it does not include balances, quantities, trades, research notes, or lesson activity. Opening the app can catch up a missed date.

Company logos

Public App Store builds are configured so the app does not request company images directly from Logo.dev. Internal TestFlight builds used for product testing may enable that path. When enabled, Logo.dev receives the device IP address, requested company domain or ticker, and request time. It does not receive balances, trades, notes, or a personal StockSim profile. If a logo cannot load, the app shows a bundled mark or letter instead.

Children and families

StockSim is designed for family learning without accounts, advertising, chat, or a news feed. The app does not ask a child for a name, age, address, school, phone number, or location. A parent or guardian should help decide whether and how a child uses the app and device email.

Your choices

You can stop network requests by taking the device offline, and you can remove locally stored app records by deleting the app or using its reset controls as described in Support. Because StockSim has no user account or cloud portfolio, it cannot restore deleted practice records from a server.

Changes to this policy

This page will be updated if StockSim’s public data flow changes. The effective date at the top identifies the current version.