Third Line LLC
Third Line LLC is the developer of MarketSim.We build software that makes investing easier to understand. With MarketSim, anyone can explore the stock market and practice investing with simulated money.
Privacy Policy
Effective Date: October 12, 2026
Introduction
Third Line LLC ("we," "us," or "our") makes MarketSim, a mobile app (the "App"). We believe privacy is a fundamental human right, so the App collects only what it needs to work, and nothing like your name or email. This policy explains what that information is, how we use it, and who we share it with. By using the App, you agree to this policy.
We Don't Ask Who You Are
The App doesn't ask for your name, email address, phone number, or a password. Your account is identified by a random ID our servers assign, and the key that signs you in is saved to your iCloud Keychain.
Information We Collect
Account Data: your random account ID, and a key Apple's App Attest issues so our servers can confirm your account was created by a genuine copy of the App.
App Content: what you create in the App, such as portfolios, orders, and watchlists. This is stored on our servers so it syncs across your devices. If you move over from an older version of the App that kept data only on your device, that data is copied to our servers.
Push Tokens: if you allow notifications, the token Apple gives us to send them to your device.
Purchase Data: when you subscribe or make a purchase, Apple sends us a transaction ID and an expiration date so we can unlock what you bought. Apple handles payment, and we never see your payment details.
Diagnostics: crash reports from the App, collected by Firebase Crashlytics (Google), and request, error, and performance data from our servers, including IP addresses, collected by Laravel. They help us find and fix bugs.
Analytics: how the App is used, such as sessions, screens viewed, device and app version, and approximate location, collected by Firebase Analytics (Google). It isn't linked to your account.
Advertising Data: the free version of the App shows ads from Google AdMob. AdMob may collect your device's advertising identifier, but only if you allow tracking. It also collects your approximate location and data about ad impressions.
Support Email: if you email us, we receive what you send, including the account ID and device details the App fills in.
How We Use Your Information
We use this information to run the App, sync your data, send notifications you've allowed, unlock purchases, fix bugs, understand how the App is used, and show ads. If you're in the EU or UK, we do this to provide the App you asked for, with your consent for personalized ads, and in our legitimate interest in keeping the App working and improving it.
We don't sell your information for money. Under California law, showing personalized ads through AdMob may count as "sharing" your information. You can opt out by declining tracking.
Sharing Your Information
We share information only with service providers that help us run the App:
Google (AdMob and Firebase): for ads, analytics, and crash reporting. To learn how Google uses information, visit www.google.com/policies/privacy/partners.
Apple: for notifications, purchases, and App Attest.
Laravel: hosts and monitors our servers and databases.
Your information is processed in the United States. We may also disclose information if the law requires it.
Keeping Your Information
We keep your account and its content for as long as your account exists. Diagnostics and analytics are kept for a limited time, no longer than 14 months.
Your Choices
Tracking: the App asks before it allows tracking. You can change your answer anytime in Settings › Privacy & Security › Tracking.
Ad Consent: where the law requires it, you can review your ad choices in the App's privacy options.
Notifications: you can turn notifications off in Settings.
Deleting Your Account: you can delete your account in the App. Your account and everything in it is permanently removed from our servers within 30 days. Limited logs and backups may be kept for a short time after that.
Your Rights
You can ask to see, correct, delete, or get a copy of your information, or object to how we use it, by emailing us with your account ID. If you're in the EU or UK, you can also complain to your local data protection authority.
Security
We protect your information by design:
Nothing to steal. We don't store your name, email, phone number, or a password.
Encrypted in transit. Everything between the App and our servers travels over HTTPS.
Genuine devices only. Our servers use Apple's App Attest to confirm that new accounts come from a real copy of the App on a real Apple device.
You control deletion. Deleting your account permanently removes it from our servers within 30 days.
No system is perfectly secure, but we work to keep your information safe.
Children's Privacy
The App is not intended for anyone under 13. We do not knowingly collect information from anyone under 13.
Changes to This Policy
We may update this policy from time to time. When we do, we'll post the new version here and update the effective date above.
Contact Us
If you have questions about this policy, contact us at contact@thirdlinellc.com.