Effective Date: January 7, 2026
TrenchCalc ("the app") is a utility tool designed for engineering professionals to calculate trench volumes and backfill estimates. We value your privacy and only collect the minimum data necessary to deliver core functionality.
TL;DR: We collect your Apple or Google account info for login and subscription management. We use location services for weather information, which is provided by Open-Meteo. Our AI-powered Site Diary feature uses OpenAI to generate entries from your voice recordings—your transcript, project name, location, and date are sent to OpenAI's servers in the United States. Project calculations are stored locally on your device. We don't show ads or sell your data.
Table of Contents
- 1. Information We Collect
- 2. How We Collect Information
- 3. Purpose for Collection, Use, and Disclosure
- 4. Third-Party Services
- 5. What We Do Not Collect
- 6. No Marketing Communications
- 7. No Advertising
- 8. Do Not Track
- 9. Consequences of Not Providing Information
- 10. Data Retention
- 11. Your Rights
- 12. Australian Privacy Rights
- 13. Residents of Certain U.S. States
- 14. European Residents
- 15. Data Security
- 16. Data Processors
- 17. International Data Transfers
- 18. Children's Privacy
- 19. Data Breach Notification
- 20. Changes to This Policy
- 21. Privacy Complaints
- 22. Contact Us
Information We Collect
- Authentication: When you sign in, we use Firebase Authentication (provided by Google) to securely manage your login. You can sign in using Apple Sign In or Google Sign In. We collect your account identifier and email address (or Apple's private relay email if you choose to hide your email) to authenticate your account. All authentication data is stored in Australia (Sydney region).
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Location Information: If you enable location services, we collect your device's GPS coordinates to provide weather information and location context for site diaries.
Your location data is shared with the following services:
- Open-Meteo: Receives your precise latitude and longitude coordinates to provide weather data. See Open-Meteo Terms & Privacy
- OpenAI: Receives your location as part of AI-assisted diary generation (see AI Features below)
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AI Features: The Site Diary feature uses OpenAI (GPT) to generate diary entries from your voice recordings. When you use this feature, the following data is sent to OpenAI's servers in the United States:
- Your voice transcript
- Project name
- Date
- Location (if provided)
We have configured our OpenAI integration so your data is not used to train OpenAI's models. - Project Information: Project details, calculations, and site data are stored locally on your device. This data is not uploaded to our servers.
- Purchases: We use RevenueCat to manage your subscription status. RevenueCat receives your email address to link your subscription across devices, along with purchase and renewal events from the app stores (Apple App Store and Google Play). RevenueCat is a US-based service. We do not receive your payment card details directly—these are handled by Apple or Google. See RevenueCat's Privacy Policy.
- Anonymous Feedback: If you delete your account, you may optionally leave feedback. This is stored anonymously and cannot be linked back to your identity.
How We Collect Information
We collect personal information in the following ways:
- Directly from you: When you create an account (using Apple Sign In or Google Sign In), sign in, use app features, or contact us for support
- Through app usage: When you use TrenchCalc features, such as Site Diary voice transcription, weather lookup, or subscription management
- From third-party services: We receive subscription status information from RevenueCat, authentication data from Firebase Authentication (Google), account information from Apple or Google when you use social login, weather data from Open-Meteo, and AI-generated content from OpenAI
Where reasonable and practicable, we collect personal information directly from you. We will notify you if we collect information from third parties not disclosed in this privacy policy.
Purpose for Collection, Use, and Disclosure
We collect, hold, and use your personal information for the following purposes:
- To provide services: To deliver TrenchCalc functionality, including authentication, subscription management, weather information, AI-powered diary generation, and other app features
- To process transactions: To manage your subscription status and payment processing through third-party services
- To improve our services: To analyse usage patterns, fix bugs, and enhance app performance and features
- To communicate with you: To respond to your inquiries, provide customer support, and send important service-related notifications
- To comply with legal obligations: To meet our legal and regulatory requirements, including data protection laws
- To protect our services: To detect and prevent fraud, abuse, and security threats
We disclose your information to the third-party service providers listed in the "Third-Party Services" section solely for the purposes stated above and under appropriate data processing agreements.
Third-Party Services
TrenchCalc uses the following third-party services:
Authentication
- Firebase Authentication (Google): Secure user authentication. Data is stored in Australia (Sydney region). See Firebase Privacy Policy
Payments
- RevenueCat: Subscription and purchase management. US-based service. See RevenueCat Privacy Policy
Weather Data
- Open-Meteo: Provides weather forecasts based on your GPS coordinates. Open-Meteo is based in the EU. See Open-Meteo Terms & Privacy
AI Processing
- OpenAI: Powers the AI-assisted Site Diary feature, generating diary entries from your voice transcripts. US-based service. See OpenAI Privacy Policy
These services have their own privacy policies and handle your data according to their respective terms and applicable data protection laws.
What We Do Not Collect
- We do not store trench calculation data in the cloud—calculations remain on your device
- We do not access your device contacts, photos, or files (except photos you explicitly add to site diaries)
- We do not show ads or track you across other apps
- We do not sell your personal information to third parties
- We do not use Firebase Analytics or Crashlytics
We share data with third-party service providers only as described in this policy and solely to provide our services.
No Marketing Communications
TrenchCalc does not send marketing emails, promotional messages, newsletters, or any other marketing communications. We only send essential service-related notifications (such as account verification or important policy updates) when necessary.
No Advertising
TrenchCalc does not display advertisements, use targeted advertising, or sell your personal information to advertisers. We do not use your data for advertising purposes, and we do not share your information with advertising networks or marketing companies.
Do Not Track
Your browser settings may allow you to transmit a "Do Not Track" signal when you visit various websites. Like many websites, our website is not designed to respond to "Do Not Track" signals received from browsers. To learn more about "Do Not Track" signals, you can visit www.allaboutdnt.com.
Consequences of Not Providing Information
Providing personal information is generally optional, but certain features require specific data to function:
- Account creation: An Apple or Google account is required to create an account and access premium features
- Subscription management: Subscription status information is required to provide access to premium features
- AI Diary generation: Voice transcripts and project information are required to generate AI-assisted diary entries
- Weather features: Location information is required to provide weather data (you can enter coordinates manually)
If you choose not to provide requested information, we may not be able to provide you with certain features or services. You can use the free tier of TrenchCalc without creating an account, but account creation is required for premium features.
Data Retention
You may delete your account at any time from the profile screen. This removes all login data from our authentication system.
- Account Data: Retained until account deletion
- Anonymous Feedback: If submitted during account deletion, this is not linked to your user ID and cannot be deleted
- Third-Party Data: Data held by our third-party service providers (RevenueCat, OpenAI, Open-Meteo) is subject to their respective retention policies
Your Rights
Under GDPR, Australian Privacy Act, and other privacy laws, you may have the right to:
- Access: Request a copy of your personal information
- Rectification: Request correction of any inaccurate data
- Erasure: Delete your account and associated data at any time (right to be forgotten)
- Portability: Export your data in a machine-readable format
- Object: Object to processing of your personal information
- Opt Out: Opt out of optional data collection
How to Exercise Your Access and Correction Rights
To request access to or correction of your personal information:
- Contact us: Send an email to support@engsitetools.com with your request
- Proof of identity: We may require proof of identity to ensure personal information is provided only to the correct person and to protect the privacy of others
- Fees: No fees are charged for access or correction requests
- Response: We will respond to your request in accordance with applicable privacy laws
- Appeals: If we deny your access or correction request, we will provide written reasons. You may lodge a complaint about this decision (see "Privacy Complaints" section below)
Australian Privacy Rights
TrenchCalc is an Australian application and we comply with the Australian Privacy Act 1988 (Cth) and the Australian Privacy Principles (APPs). If you are located in Australia, you have the following rights:
- Access: You have the right to request access to the personal information we hold about you
- Correction: You have the right to request correction of any inaccurate, incomplete, or out-of-date personal information
- Complaints: You have the right to make a complaint about how we handle your personal information. If you are not satisfied with our response, you can contact the Office of the Australian Information Commissioner (OAIC) at www.oaic.gov.au
- Anonymity: Where lawful and practicable, you have the right to interact with us anonymously or using a pseudonym
- Cross-border disclosure: We disclose personal information to overseas recipients (United States and European Union) as described in this policy. We take reasonable steps to ensure overseas recipients handle your information in accordance with Australian privacy law.
To exercise your Australian privacy rights, contact us at: support@engsitetools.com
Residents of Certain U.S. States
If you are a U.S. resident, depending on the state you live in, you may have some or all of the rights listed below in relation to information that we have collected about you. However, these rights are not absolute, and in certain cases, we may decline your request as permitted by law, including in the event you reside in a state that does not currently grant you these rights.
- Right to Access: You may have a right to request that we confirm whether we process information about you and give you access to that information in a portable and, to the extent technically feasible, readily usable format that allows you to transmit the information to another business without impediment.
- Right to Delete: You may have a right to request that we delete information we maintain about you.
- Right to Correct: You may have a right to request that we correct inaccurate information we maintain about you.
- Right to Opt-out of Targeted Advertising, Profiling, or Selling: You may have a right to opt-out of the processing of your information for the purposes of targeted advertising, the profiling of your information in furtherance of decisions that produce legal or similarly significant effects, and/or the sale of your information (as all such terms and concepts are defined under applicable law). We do not engage in targeted advertising, profiling, or selling of personal information.
You may exercise any of these rights by contacting us using the information provided in the "Contact Us" section below. We will not discriminate against you for exercising any of these rights. We may need to collect information from you to verify your identity, such as your email address, government issued ID, or date of birth, before providing a substantive response to the request. Depending on your location, you may designate, in writing or through a power of attorney document, an authorised agent to make requests on your behalf to exercise your rights. Before accepting such a request from an agent, we will require that the agent provide proof you have authorised them to act on your behalf, and we may need you to verify your identity directly with us.
In addition, you may have the right to appeal our decision regarding a request related to these rights by contacting us using the information provided below. When you submit a request or launch an appeal, we will limit our collection of your information to only what is necessary to securely fulfil your request or process your appeal. We will not require you or your authorised agent to pay a fee for the verification of your request or appeal.
European Residents
Data Transfers
We are based in Australia. If you are using the Services from outside Australia, please be aware that the information we collect from you may be transferred to, stored, and processed in countries outside your country of residence, including:
- Australia: Firebase Authentication and primary data storage (Sydney region)
- United States: OpenAI (AI processing), RevenueCat (subscription management)
- European Union: Open-Meteo (weather data)
We implement appropriate safeguards, including Standard Contractual Clauses (SCCs) for EU data transfers where applicable, and comply with applicable data protection laws, including the Australian Privacy Act 1988 and GDPR.
Data Subject Rights
If you are located in the EEA or the UK, you have certain rights in relation to your personal data. Please note that a number of these rights only apply in certain circumstances, and all of these rights may be limited by law. To exercise any of these rights, you can contact us at the email address provided in the "Contact Us" section below:
- Access: You have the right to access the personal data we hold about you, and to obtain information about how we use it, and who we share it with.
- Portability: You have the right to receive a copy of the personal data we hold about you and to request that we transfer it to a third party, in certain circumstances and with certain exceptions.
- Correction: You have the right to correct any of your personal data we hold that is inaccurate.
- Erasure: In certain circumstances, you have the right to delete the personal data we hold about you.
- Restriction of processing to storage only: You have the right to require us to stop processing the personal data we hold about you, other than for storage purposes, in certain circumstances.
- Objection: You have the right to object to our processing of your personal data in certain circumstances.
- Objection to marketing: You can object to marketing at any time. Please note that we do not send marketing communications.
- Withdrawal of consent: Where we rely on consent to process your personal data, you have the right to withdraw this consent at any time by contacting us at the email address provided below.
- Complaints: You have the right to complain to your local data protection authority about how we process your personal data. We hope you will contact us first so we can resolve any issues.
Legal Basis for Processing (GDPR)
We process your personal data on the following legal bases:
- Contract: Processing necessary to provide you with our services
- Legitimate interests: Processing necessary for our legitimate business interests, such as improving our services and preventing fraud
- Consent: Where you have given consent for specific processing activities
- Legal obligation: Processing necessary to comply with applicable laws
Data Security
We implement industry-standard security measures to protect your data:
- Encryption: All communications with our servers are encrypted using HTTPS/TLS
- Authentication: Firebase Authentication (Google) with industry-standard security practices
- Access Controls: Role-based access control for all data
- Secure Storage: All data stored with encryption at rest
- Regional Storage: Authentication data stored in Australia (Sydney region)
Data Processors
We use the following third-party services that process your data:
| Service | Purpose | Location | Privacy Policy |
|---|---|---|---|
| Firebase (Google) | Authentication | Australia (Sydney) | Firebase Privacy |
| RevenueCat | Subscription management | United States | RevenueCat Privacy |
| Open-Meteo | Weather data | European Union | Open-Meteo Terms & Privacy |
| OpenAI | AI diary generation | United States | OpenAI Privacy |
These services process data under appropriate data processing agreements and in accordance with applicable privacy laws.
International Data Transfers
As an Australian-based service with international users, your data may be transferred to and processed in countries outside your country of residence:
| Data Type | Destination | Service |
|---|---|---|
| Authentication data | Australia (Sydney) | Firebase |
| Subscription data | United States | RevenueCat |
| Location coordinates | European Union | Open-Meteo |
| Diary transcripts, project info, location | United States | OpenAI |
We implement appropriate safeguards through:
- Standard Contractual Clauses (SCCs) for EU data transfers where applicable
- Data processing agreements with all third-party processors
- Compliance with the Australian Privacy Act 1988 (APP 8 - cross-border disclosure)
- Compliance with GDPR requirements for European users
Children's Privacy
TrenchCalc is designed for engineering professionals and is not intended for children under 13 years of age. We do not knowingly collect personal information from children under 13. If you believe we have collected information from a child under 13, please contact us immediately at support@engsitetools.com and we will delete such information.
Data Breach Notification
In the event of a data breach that affects your personal information, we will:
- Notify affected users as soon as reasonably practicable
- Notify the Office of the Australian Information Commissioner (OAIC) within 72 hours where required under the Notifiable Data Breaches scheme
- Notify relevant data protection authorities in other jurisdictions where required by law
- Provide details about the breach and recommended mitigation steps
Changes to This Policy
We may update this privacy policy from time to time to reflect changes in our practices or applicable laws. We will notify you of significant changes through the app or via email. The "Effective Date" at the top of this policy indicates when it was last updated. Continued use of TrenchCalc after changes constitutes acceptance of the updated policy.
Privacy Complaints
If you have concerns about how we handle your personal information or believe we may have breached privacy laws, you can lodge a complaint with us:
- Email: support@engsitetools.com
- Subject: Please include "Privacy Complaint" in your email subject line
We will investigate your complaint and respond to you within 30 days. If you are not satisfied with our response, you have the right to escalate your complaint to the relevant data protection authority in your jurisdiction:
- Australia: Office of the Australian Information Commissioner (OAIC) — www.oaic.gov.au
- United Kingdom: Information Commissioner's Office (ICO) — ico.org.uk
- European Union: Your local data protection authority (DPA)
- United States: Federal Trade Commission (FTC) — www.ftc.gov
Contact Us
If you have any questions or concerns about this privacy policy or wish to exercise your privacy rights, please contact us at:
Email: support@engsitetools.com
Business Location: Australia
Thank you for using TrenchCalc. We are committed to protecting your privacy.
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