Privacy Policy

We collect information you provide, information created when you use an account feature, limited technical information generated by the Service, and information supplied by payment or authentication providers.

Depending on the features you choose, this may include:

• Your name, username, email address, profile picture, Firebase identifier, authentication provider and email-verification status.
• Optional profile details you choose to provide, such as first and last name, phone number, date of birth, city, region, country, institution, certification or licence details, locale, language, theme and simulator preferences.
• Where Classroom is enabled: classroom name, owner, co-teacher and student identifiers, invited email address, seat status, join-code activity, assignment dates, work-file associations, explicitly submitted circuit copies, submission status, feedback and CSV-export activity. Owners and authorized co-teachers can see records needed to manage their classroom, including submitted work; private working drafts and unrelated personal learning records are not part of that view.
• Plan, entitlement, subscription, invoice, payment and refund references; support messages; newsletter email, locale, source and subscription status. Stripe handles full payment-card details; DigiSim does not store full card numbers or card security codes.

The Service may generate or receive:

• IP address and request time for security, rate-limiting, troubleshooting and fraud prevention.
• Browser type and version, operating system, device category and application version.
• Pages, labs and features used, navigation events and approximate session timing.
• Lesson access and progress records needed to resume and display your learning state.
• Authentication, account, purchase and entitlement events and their status.
• Cookie-consent choice and timestamp, language, theme, sound and other saved preferences.
• Client error reports, which may include an error message, stack trace, current page URL, user agent and application version. Do not place secrets or sensitive personal information in circuit names or URLs.
• Security events, failed sign-in attempts, attempted email address, IP address, reason and timestamp.
• Optional Google Analytics events only after analytics consent. We do not use advertising cookies or sell personal information.

Browser-local persistence differs by lab: Logic keeps local circuits, Electricity, Analog and Relay each keep one local draft. DigiSim cannot access work that remains only on your device. If you choose a supported cloud save, unlisted link, public-gallery publishing, or another server feature, we store the circuit document and related metadata needed to provide it. Where cloud save is supported, current limits are 5 on Free and 250 on Pro or Founder; Classroom limits apply only to a confirmed entitlement. You can delete individual cloud saves and export a project file only where the selected lab provides those controls.

We use cookies, local storage, session storage and IndexedDB for authentication, local projects, preferences and consent records. Google Analytics is loaded only after consent. We do not use advertising cookies. Names, purposes and durations are listed in our Cookie Policy.

Firebase Authentication, supplied by Google, manages sign-in. Google Identity Services may offer its official button or One Tap on selected signed-out pages; a successful Google choice is converted into a Firebase session before DigiSim creates or opens the account. The Service also offers email-and-password sign-in.

Identity information received:

• Email address, email-verification status and a provider-specific account identifier.
• Name and profile picture when supplied by the provider or entered by you.
• Authentication-provider and security metadata needed to validate and protect the session.

Why we process it:

• To create, authenticate and secure your account.
• To connect your entitlements, cloud saves and preferences to the correct account.
• To send password, verification, security and service messages.
• To detect duplicate, compromised or abusive accounts.

Provider controls:

• Google supplies Firebase Authentication and processes sign-in information under Google's Privacy Policy and the applicable service terms.
• Google sign-in requests only OpenID, email and basic-profile permissions; it does not give DigiSim access to Drive, Gmail or other Google content.
• You can review connected access in your Google Account settings.

Credentials and session storage:

• DigiSim does not receive or store your Google password. Email-and-password credentials are handled by Firebase Authentication rather than DigiSim's application database.
• Firebase may keep authentication state in browser IndexedDB until you sign out, delete the account or clear browser data.
• DigiSim stores the account identifiers and profile information needed to operate the Service, but not full payment-card details.

Your choices:

• You may use email-and-password instead of Google sign-in.
• Sign out on shared devices and contact support if you believe an identity-provider account has been compromised.

Under UK data-protection law, we process personal information only where a lawful basis applies:

• Contract: create and authenticate accounts; provide labs, lessons, cloud saves, sharing, Classroom, entitlements, billing support and requested communications.
• Contract and legal obligation: process purchases, subscriptions, invoices, refunds, tax and accounting records.
• Legitimate interests: secure the Service, prevent fraud and abuse, enforce fair-use limits, investigate errors and maintain reliability, balanced against your rights.
• Legitimate interests: understand aggregate feature performance and improve the Service using proportionate operational data.
• Consent: use Google Analytics and its non-essential identifiers. Refusing or withdrawing analytics consent does not affect core Service access.
• Consent or applicable electronic-marketing rules: send newsletters or promotional email. You can unsubscribe at any time.
• Legal obligation: respond to valid legal requests and exercise data-protection rights.
• Legitimate interests or legal obligation: establish, exercise or defend legal claims and preserve evidence where necessary.
• Consent or your direction: publish a circuit, create a share link, connect an identity provider or make another optional disclosure you request.

We do not sell personal information. We disclose information needed to operate the Service to the providers described below, to authorized classroom staff for the enabled workflow, to people you choose to share with, during a properly protected business transaction, or where law requires it. A provider may act on our instructions for a service and may also have independent responsibilities, such as payment fraud prevention or compliance with law; its role depends on the processing involved.

The providers used for a particular interaction depend on the feature, location and deployment. Key categories are identity, infrastructure, payments, communications and consent-based analytics.

Current key providers and purposes:

Google Firebase and Google Identity Services — account authentication and session protection; Google Firebase App Check and reCAPTCHA Enterprise — automated-abuse prevention and request protection, including on some public pages before sign-in; Stripe — hosted checkout, subscriptions, invoices, fraud prevention and refunds; Amazon Web Services — application hosting, databases, object storage, logging and email infrastructure; Cloudflare — website and asset delivery, network security and request diagnostics; Postmark and Resend — transactional or support email where configured; Google Analytics — optional audience and product analytics after consent. Google-hosted fonts receive the connection information needed to deliver fonts. Our Google Forms contact link opens a Google-hosted form; information you submit there is also processed to handle your request. Provider services and external sites have their own privacy terms. See Google, Stripe, AWS and Cloudflare. These disclosures do not make optional analytics necessary.

If DigiSim is reorganised, financed, sold or combined with another business, relevant information may be disclosed under confidentiality and transferred as part of that transaction. We will notify affected users before a new controller uses personal information in a materially different way.

We may preserve or disclose information where reasonably necessary to comply with law, a court order or a valid public-authority request; protect users, DigiSim or the public; investigate fraud or security incidents; or establish, exercise or defend legal claims. We assess requests and disclose only the information legally required.

We may disclose information when you make it public, create an unlisted link that anyone with the URL can view, accept a Classroom invitation, ask us to communicate with another party, or give a separate, informed consent. You may withdraw consent for future processing, but this does not make earlier lawful processing unlawful.

DigiSim does not currently provide real-time co-editing. Logic and Electricity can create an <strong>unlisted link</strong> that anyone with the URL can view; plan-based links expire after 14 days on Free or 365 days on Pro or Founder, so revoke one sooner if it is disclosed accidentally. Relay uses a separate revocable public-link model, while Analog sharing is not currently documented. <strong>Public-gallery publishing</strong> is opt-in and exposes the circuit name and design, your DigiSim username, optional description, thumbnail and view count to anyone. Unpublishing removes the listing, although caches may take time to refresh. <strong>Classroom</strong> is limited to Digital Logic Lab, with annual seat subscriptions and administrator-invoice activation. Owners and authorized co-teachers can manage invited member details, seats, assignments, explicitly submitted copies, submission status, feedback and permitted CSV exports. Saving a private draft does not submit it. The classroom view does not expose private working drafts, unrelated circuits or unrelated personal learning progress.

We use proportionate technical and organisational measures such as HTTPS, access controls, provider-managed authentication, restricted administrative access, monitoring and backups. No internet service can promise absolute security. Keep exported files and share links secure, use a unique password, sign out on shared devices and report suspected compromise promptly.

Retention depends on the purpose of the record, whether you still use the relevant feature, an outstanding request or dispute, and any legal duty to keep it. The criteria below describe that assessment. A share-link expiry, subscription cancellation or loss of account access does not by itself erase all associated records. Contact us for the retention information relevant to a particular record or to request deletion.

Local browser data: Projects and preferences that remain only in your browser stay until you delete them, clear site data or the browser removes them. DigiSim does not control that retention.

Server records: The following criteria apply:

• Account and cloud content: used while the account or requested feature is active. You can remove supported cloud items and request account closure or erasure. Related records and backup copies may require separate assessment; deletion is not an immediate purge of every system. Unlisted links expire as stated above; expiry stops link access rather than promising deletion of the underlying project.
• Payments and accounting: retained as needed for tax and accounting duties, refunds, chargebacks and disputes. The period depends on the record and the applicable legal requirement. Full payment-card details remain with Stripe.
• Support, security and diagnostics: retained according to the request or incident, the need to investigate repeated abuse or defend a claim, and applicable legal duties. Ask us for the period or criteria for the records relevant to your request.
• Classroom and newsletter: classroom membership, invitations, assignments, submissions and feedback are assessed against the enabled teaching workflow, class closure, an applicable institutional arrangement and legal duties. Closing a class or removing a member is not the same as erasing every record. Newsletter use stops on unsubscribe; limited suppression and consent evidence may remain where needed to honor the opt-out or demonstrate compliance.

Some DigiSim labs provide project-export tools for copies you control; Electricity currently has no project-download control. File structure and extension differ by lab and version, and some exports are policy-gated. Data-protection portability is a separate right: where it applies, you may request personal information you supplied in a structured, commonly used, machine-readable format.

Email support@digisim.io to request account closure or an erasure assessment. We may ask for proportionate information to verify your identity and clarify the request. We assess the relevant account, cloud content, sharing, Classroom, payment, security and provider records, and explain any applicable exception or lawful retention. Closure, subscription cancellation and erasure are separate actions; an email request does not instantly delete every record or cancel billing. You may use available controls to revoke links or remove content promptly and export work you want to keep, but doing so is not a condition of making a privacy request. Backup and provider records may require separate handling. We will explain the outcome and any outstanding retention relevant to your request within the applicable legal response period.

Depending on where you live and the lawful basis, you may have rights to be informed; access a copy; correct inaccurate data; erase data; restrict processing; receive portable data; object to legitimate-interest or direct-marketing processing; withdraw consent; and challenge a qualifying solely automated decision. We do not use personal information to make solely automated decisions that produce legal or similarly significant effects.

You can update certain profile and preference fields in account settings. For a copy, correction, or restriction request, email support@digisim.io. We may request proportionate information to verify identity and protect the account before responding.

Where processing is automated and based on consent or contract, you may ask for personal information you provided in a structured, commonly used, machine-readable format, subject to the rights of others and applicable exceptions. Circuit-project export is a separate product feature and is available only in labs that provide it.

You may ask us to erase personal information where it is no longer needed, consent is withdrawn and no other basis applies, processing was unlawful, or another legal ground applies. We may retain limited records where required by law or needed for security, legal claims or another statutory exception, and will explain a refusal.

You may object to processing based on legitimate interests and may object to direct marketing at any time. Contact us first so we can investigate. You also have the right to complain to the UK Information Commissioner's Office at ico.org.uk/make-a-complaint, or to the data-protection authority where you live or work when applicable.

Use Cookie Settings to reject or withdraw analytics consent. Use the unsubscribe control in a marketing email or contact us to stop newsletters. Essential service, security, billing and legal messages may still be sent where needed to operate your account or contract.

DigiSim is an educational service that may be used by people under 18. Analytics is off until a choice to accept it, and public-gallery publishing is optional. These defaults do not replace the safeguards or permission required for a particular child. A child under 13 must have authorization from a parent or legal guardian to create a personal account, together with any permission required by local law. Where UK law requires consent for an online service offered directly to a child under 13, that consent must be given or authorized by a person with parental responsibility; school approval alone does not replace it. Schools must have authority to arrange student access, provide their own appropriate notices and confirm the safeguards for Classroom. The standard signup form does not itself verify age or parental authority. Contact support@digisim.io about child or school use, unauthorized accounts or a child’s privacy request. Do not put sensitive personal information in circuit names, public profiles or shared work.

DigiSim is based in the United Kingdom. Providers such as Google, Stripe, AWS and communications vendors may process information in the United Kingdom, European Economic Area, United States or other locations where they operate.

The lawful mechanism for a transfer depends on the provider, destination and service. Applicable mechanisms can include an adequacy decision or contractual safeguards such as the UK International Data Transfer Agreement, the UK Addendum to standard contractual clauses, or EU standard contractual clauses, together with any assessment required by law. Listing a mechanism here is not a claim that every provider or transfer uses the same mechanism.

We do not rely on your acceptance of this Privacy Policy as consent to an international transfer. You may contact us for more information about the safeguard relevant to your information and how to obtain a copy, subject to permitted redactions.

Contact us about this policy or to exercise a privacy right. For a UK data-protection request, the normal response period is one month. We will explain if proportionate identity checks, a permitted clarification or a lawful extension affects the deadline. Other applicable rights and response periods remain available.