Privacy Policy
Exam reminders
This optional service is separate from trial emails and saving your progress. It is for people aged 16 and over. We collect the email address you provide, your optional exam date, the scheduled reminder date and time, and a record of your consent: its wording and version, when you gave it, and when you confirmed it. We use these only to send one confirmation link and one requested study reminder with a link to a free practice question. We do not send study tips or offers or add you to a marketing list.
We rely on your consent. The reminder checkbox starts unchecked. You must confirm by email within 24 hours before we schedule a reminder. Consent is optional and does not affect access to free practice or start a trial. Trial-email choices and the removal of trial-email addresses when a trial ends are separate from this service (see section 3). Choose an exam date 4–90 days away for a reminder 3 days before it, or leave the date blank for a reminder 3 days after confirmation. Reminders are scheduled for 11 a.m. Eastern Time; delivery can be delayed by the email provider.
You can withdraw consent using the unsubscribe link in either email, without signing in, paying or giving a reason. This stops pending reminders and deletes your reminder record within 24 hours. Withdrawal does not affect processing already carried out with consent. Unsubscribe links remain usable for at least 30 days after a message. A new request requires fresh consent and confirmation.
Unconfirmed records expire after 24 hours and are deleted within the following 24 hours. Confirmed records, including the address, optional exam date and consent evidence, are deleted within 24 hours after the reminder is sent or you unsubscribe, and no later than 7 days after the scheduled reminder if delivery fails. We delete consent evidence with the reminder record. Nonidentifying total counts may remain.
Reminder records are stored privately on our server, separately from trial records, in private Vercel Blob storage. Resend, our existing email delivery provider, processes the recipient address and message to deliver these two emails; we do not send it your optional exam date. Resend stores email content and delivery logs in the United States for 30 days on its standard plans, and backups persist for 7 days. These provider records are separate from our shorter-lived reminder records. We do not use email open or click tracking for this service.
Vercel and Resend may process information in the United States. Their data processing agreements incorporate EU Standard Contractual Clauses and the UK Addendum for applicable international transfers. You can read the Vercel and Resend agreements using the links below. Reminder consent is not consent to unrelated marketing or advertising.
The reminder page runs no advertising or analytics scripts. We do not sell or share reminder information for cross-context behavioral advertising, or attach names, trial or customer identifiers, referral data or browsing activity to reminder records. For abuse prevention, we briefly retain keyed codes derived from the email address and request IP address, and request counts; these are separate from reminder records and deleted within 48 hours. The raw IP address is not stored in these records. Standard hosting security logs may include IP addresses and browser information, as described elsewhere in this policy.
Use the contact address at the top of this policy to request access, correction or deletion, or to exercise applicable privacy rights, without losing access to free practice. Email requests follow our existing response timeline, typically within 30 days. Where applicable you may request restriction of processing, object, request a portable copy, or complain to your data protection authority. The operator and contact details in this policy apply to this service.
Provider details: Vercel DPA, Resend DPA, Resend retention.
1. Progress and settings on your device
StatsDrill stores lessons read, answers given, flashcard grades, Match results, activity completions, practice-exam attempts and preferences in your browser under keys beginning with statsdrill.progress.v1. Theme, trial state, consent choice, campaign tags (section 7), random identifiers for your trial and the visit counter (sections 2 and 5), a sign-in token if you save your email, and any paid-access token are also kept in your browser. Your study answers and detailed progress are not uploaded to our server unless you save your email (section 3).
If you save your email, we keep a copy of your progress on our servers as described in section 3.
2. Trial records
A free trial starts without a card, email or account; continuing it past Chapter 1 requires saving an email (section 3). Our server records a randomly generated device identifier, the trial start and end dates, and whether the record is a test. We use this to return the same trial when you revisit and to avoid starting a new trial each time. We keep the identifier in your browser and in a secure, HTTP-only sd_tdev cookie scoped to our API for up to one year. Trial records are stored in StatsDrill’s own private Vercel Blob storage. They have no automatic deletion date and stay until you ask us to remove them. Clearing site data can remove your local access and progress; it does not delete records already held by our service providers.
To stop accidental duplicate free trials, when you start a trial we briefly keep a one-way scrambled code made from your IP address and browser. It can't be turned back into your IP address and it isn't linked to your account. We compare it for 15 minutes; after that it is deleted automatically the next time a trial starts.
3. Email, saved progress and trial emails
You can study the free chapters (Chapters 1 and 13) without an email and skip the optional “Save your progress” prompts. Continuing an active trial into Chapter 2 and the other trial chapters requires saving an email. When you save one, we receive the address, derive a protected identifier from it (a keyed hash), and store with that identifier your trial start and end dates, the date of your last visit, your trial-email choice and any unsubscribe, whether that email bought a plan, and a copy of your study progress: answers and results, lessons completed, review schedules and study preferences, without your profile name. We use this to save your progress, restore it and the same trial in another browser or on another device, keep the original trial end date, and allow one free trial per email.
We email you a sign-in link to restore your progress, including when you move from Instagram’s or Facebook’s in-app browser to Safari or Chrome. Links expire after 15 minutes and can be used once; keep them private. Saving your email is not consent to unrelated marketing.
If you tick “Optional: email me a study check-in and a before-expiry heads-up that includes paid-plan options during my active trial, when eligible. Unsubscribe anytime.”, we store your address privately on our server with your trial record so we can contact you about your trial: a study check-in and a reminder before it ends. We don’t send them after you buy a plan. You can unsubscribe anytime with the link in every email or by replying. Unsubscribing stops the emails; it does not remove your address from the record, except an address kept for the discount offer below, which is deleted right away. If you tick neither this box nor the discount-offer box below, we use your address to send your sign-in link and do not store it in plain text. We keep only the protected identifier.
One discount offer (optional). When you save your email during a running free trial, you can also tick “Email me once with a discount offer if I haven't been back 7+ days after my trial ends.” It is a separate box from the trial-email box above. It starts unticked, and ticking it is not needed for anything else. If you tick it, we add to your trial record that you ticked the box, when, the version of the wording you saw and that trial's end date, and we keep your email address with the record in readable form. We also record the calendar day (in UTC) of your most recent visit to StatsDrill in a browser where you saved that email (when the app saves or syncs your progress there, or you open a sign-in link): the day only, with no time, pages, IP address or device details. This is in addition to the last-visit date described above. We use these only to send you one email, an advertisement with 30% off the first month of the $10 monthly plan, 7 to 30 days after your trial ends, and only if you haven't been back for at least 7 days. We send it at most once, and not at all if you have bought a StatsDrill plan or a course bundle that includes StatsDrill (we check with Stripe first) or unsubscribed. We delete the address and that visit day 30 days after your trial ends, in our daily cleanup (usually within a day), or right away if you unsubscribe with the link in the email or by writing to support@outermilelabs.com. If you bought a plan with that email, the address is instead kept as described below for buyers. The record that you ticked the box and when stays with the protected identifier and trial dates as proof of your choice, and an unsubscribe stays recorded so the offer is never sent later. The offer link carries campaign tags so we can count visits from it; we don't track whether you open the email. If the offer isn't available when you save, we tell you and store nothing new. If you don't tick the box, nothing new is stored.
Retention: if we stored your address, our daily cleanup removes it from the trial record once the trial ends, unless you bought a plan with that email. If you did, we keep it until you ask us to remove it. If you ticked the discount-offer box, your address is instead kept until 30 days after your trial ends and then removed, with the last-visit day for that offer, by the same daily cleanup (usually within a day), unless you bought a plan with that email; unsubscribing removes them right away. The protected identifier and trial dates stay until you ask us to remove them, so the same email does not get a second free trial. Saved progress is deleted after 12 months without activity. Records of used sign-in links are deleted by the daily cleanup after 24 hours. Clearing browser data does not delete the saved server copy. To see or remove what we hold, contact support@outermilelabs.com.
We use Resend to deliver these emails, so it receives your address and the message each time we send one, and keeps its delivery records as described under Exam reminders. We use Vercel private Blob storage to keep these records. We do not send saved email addresses or study answers to advertising platforms.
4. Payments and billing
If you buy a plan, checkout is hosted by Stripe. Stripe collects the email, card and billing details needed to process your payment. We never see or store your card number. Stripe makes payment and subscription information available to us, including a customer identifier, the plan and semester, amount, date, and whether access is active, cancelled or refunded. We use this to unlock access, handle cancellation and refunds, and provide Stripe’s billing portal. Stripe processes information under its own Privacy Policy.
5. First-party visit and event counter
StatsDrill uses its own counter to understand visits and steps such as opening a lesson, starting a trial or opening checkout. It records a limited set of event names, source and campaign tags, phone or desktop category, whether the visit is in an in-app browser, whether it is a returning visit, and time spent on the landing page. A random browser identifier is converted to a different daily hash before storage; reporting returns aggregate counts. These records have no automatic deletion date. We do not include names, email addresses, card details, study answers or full page URLs in these event records. Global Privacy Control disables this counter, and automated browser and QA visits are excluded. We also use Vercel Web Analytics, our hosting provider's privacy-friendly analytics, to count page views; it does not use cookies and does not identify you.
6. Meta Pixel and your choice
We use a Meta pixel (which may set cookies) to improve the site and measure our ads. It records visits, trial starts, checkout starts and completed purchases (including value and currency) and sends this usage information to Meta. We turn off automatic form collection and never send names, email addresses or card details to the pixel.
Visitors in the United States: the pixel runs when the page loads. You can opt out at any time with "Your privacy choices" at the bottom of every page. Your choice is saved on this device. If your browser sends a Global Privacy Control (GPC) signal, we treat it as an opt-out and the pixel does not load. Opting out does not affect study access.
Visitors outside the United States, including Canada, and visitors whose location we can't determine: the pixel stays off unless you choose Allow on the banner. You can change your choice at any time with "Your privacy choices".
To decide which choice applies, we use the country that our hosting provider (Vercel) estimates from your connection. We do not store your IP address or location for this. The pixel is also turned off for automated visits, QA visits and preview pages.
7. Campaign links and service providers
If you arrive through a campaign link, we remember its first-touch tags in your browser for 30 days so the welcome screen can match the offer. Limited source and campaign tags may be included with the first-party counter, trial alerts and Stripe checkout metadata. Billing and trial alerts contain the event type and limited plan or source information; they exclude customer names, email addresses, IP addresses and Stripe customer identifiers.
We use Vercel for hosting, Web Analytics and private storage, Stripe for payments and billing, and Resend for sign-in, trial and discount-offer emails (section 3), and requested exam-reminder emails (see Exam reminders). Meta is used for advertising measurement as described above. Vercel may process standard request information, such as IP address, browser type and requested path, for security and operation. We also use Vercel Web Analytics to count page visits. It does not use cookies and does not identify you; Vercel processes the page address, referrer, approximate country and device/browser type to produce aggregate visit counts. We do not use Vercel Speed Insights or a session-replay tool.
8. Your choices, retention and deletion
You can clear local progress and settings through your browser’s site-data controls. Use the unsubscribe link in any trial or discount-offer email to stop those emails. Use "Your privacy choices" to opt out of (or, outside the US, decline) Meta measurement, or enable Global Privacy Control to disable both Meta measurement and our first-party counter. To ask about or request deletion of information we hold, contact support@outermilelabs.com. The sections above give the deletion rule for each record. Where no automatic deletion is stated, we keep the record until you ask us to remove it. Some payment records must be retained for tax, accounting or other legal requirements, and service providers may retain their own records under their policies.
9. Children
StatsDrill is intended for college students and adult learners. We do not knowingly collect personal information from children under 13. If you believe we have received such information, contact us so we can review and delete it where appropriate. The optional exam-reminder service is only for people aged 16 and over (see Exam reminders).
10. Changes
If this policy changes, the date above will change with it. Material changes will be announced in the app.