Last updated: April 21, 2026
Please read this disclaimer carefully before using Quick DA (the "App"). By downloading or using the App, you acknowledge that you have read, understood, and agree to the terms of this disclaimer.
Quick DA is provided as a supplemental tool for estimating density altitude. The calculations provided by this application are for informational and reference purposes only. Quick DA should not be used as the sole source of information for making safety-critical decisions.
Quick DA is designed exclusively for educational and informational purposes. The density altitude calculations, weather data, elevation data, and GPS coordinates provided by this App are intended to help users understand atmospheric conditions — they are not intended to support critical operational decisions in aviation or any other safety-sensitive application. Do not use this App as a primary or sole reference for any decision where inaccuracy could result in injury, loss of life, property damage, or legal consequences.
This App has not been approved, certified, endorsed, or reviewed by the Federal Aviation Administration (FAA), Transport Canada, EASA, or any other aviation regulatory authority. Quick DA is not a substitute for official aircraft performance charts, Pilot's Operating Handbooks (POH), Airport/Facility Directory data, or any other FAA-approved material. Pilots must always consult official manufacturer and regulatory documentation when making flight planning or operational decisions.
Location data is obtained from your device's built-in GPS hardware and is subject to limitations including atmospheric interference, signal obstruction from terrain or structures, multipath errors, and inherent device hardware constraints. Positional accuracy may range under ideal conditions as well as in degraded environments. Always verify your location using independent, certified navigation sources before making any critical decision.
Elevation data is sourced from the U.S. Geological Survey (USGS) National Elevation Dataset and is provided "as-is." This data may contain errors, outdated readings, or inaccuracies due to changes in terrain, resolution limitations, or interpolation methods. The elevation displayed in the App may not reflect actual field conditions at a given location. Always verify elevation through official or certified survey data before making decisions that depend on precise elevation.
Weather data — including temperature, dew point, and barometric pressure — is sourced from Apple WeatherKit. Real-time atmospheric conditions can change rapidly and may not be fully captured by automated weather station networks. Weather readings may be delayed, interpolated from nearby stations, or otherwise imprecise. Do not rely on weather data from this App as a substitute for official METAR, ATIS, or other certified weather reporting sources.
Density altitude calculations are mathematical approximations. The App uses a standard industry formula. However, no formula captures the full complexity of real atmospheric conditions. This calculation does not account for:
Results should be treated as estimates only.
THE APP IS PROVIDED "AS-IS" AND "AS AVAILABLE" WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED. Quick DA makes no representations or warranties regarding the accuracy, completeness, reliability, or timeliness of any information provided by the App. Your use of the App is entirely at your own risk.
To the maximum extent permitted by applicable law, Quick DA shall not be liable for any direct, indirect, incidental, special, consequential, or punitive damages — including but not limited to personal injury, loss of life, property damage, or financial loss — arising out of or related to your use of or reliance on this App, its calculations, or the data it provides. Users assume all risk associated with using this App and any decisions made based on information it displays.
You are solely responsible for verifying all data displayed by the App through independent, certified, and authoritative sources. You are responsible for understanding the limitations described in this disclaimer, for not relying solely on this App for any safety-critical decision, and for consulting qualified atmospheric and or meteorological professionals or other relevant experts before acting on any information the App provides.
This App integrates data from the following third-party services, each governed by its own terms and policies:
Quick DA is not responsible for the accuracy, availability, or continuity of any data provided by these third-party services.
If you have questions about this disclaimer, please contact: Support@QuickDA.app
Please read these Terms of Service ("Terms") carefully before downloading or using Quick DA (the "App"). These Terms constitute a legally binding agreement between you ("User" or "you") and James Watts ("Developer," "we," "us," or "our"). By downloading, installing, or using the App, you confirm that you have read, understood, and agree to be bound by these Terms. If you do not agree, do not download or use the App.
These Terms apply to all users of the App, including those who access the App after downloading it through the Apple App Store. Your use of the App is also governed by Apple's App Store Terms of Service, which are incorporated by reference. In the event of a conflict between these Terms and Apple's terms, Apple's terms shall prevail to the extent required.
These Terms should be read alongside our Disclaimer and Privacy Policy, both of which are incorporated into this agreement by reference.
Subject to your compliance with these Terms, we grant you a personal, limited, non-exclusive, non-transferable, revocable license to download and use the App on any Apple device that you own or control, for your personal, non-commercial use only.
You may not:
Any use of the App not expressly permitted by these Terms is a breach of this agreement and may result in termination of your license.
3.1 Pricing and Purchase
Quick DA is a paid application sold through the Apple App Store. The purchase price is set in USD and may vary by region based on Apple's pricing tiers. All transactions are processed exclusively by Apple; we do not handle or have access to your payment information.
3.2 One-Time Purchase
This App is offered as a one-time purchase. You pay once and receive a perpetual license to use the App on your personal devices, subject to these Terms. There are no subscriptions, recurring charges, or hidden fees associated with the core App.
3.3 Taxes
You are responsible for any applicable taxes, duties, or levies arising from your purchase. Apple may collect and remit taxes on your behalf as required by your jurisdiction.
3.4 App Store Terms Govern Payment
All aspects of your purchase — including payment processing, billing inquiries, account management, and purchase history — are governed by Apple's App Store Terms of Service. We are not party to the payment transaction and have no ability to process charges or access your billing details.
4.1 Ownership
The App, including all code, design, graphics, UI elements, text, icons, and functionality, is the exclusive property of James Watts and is protected by applicable copyright, trademark, and intellectual property laws. All rights not expressly granted to you in these Terms are reserved by the Developer.
4.2 License vs. Ownership
Your purchase grants you a license to use the App, not ownership of the App or any intellectual property within it. Purchasing the App does not transfer any ownership interest to you.
4.3 User-Generated Data
Any data you create within the App — such as saved Data Log entries — remains your property. This data is stored locally on your device. We do not claim any ownership over your personal data, and we do not transmit it to our servers.
4.4 Third-Party Content
The App integrates data and services from third parties whose content is governed by their respective licenses and terms:
5.1 Lawful Use
You agree to use the App only for lawful purposes and in compliance with these Terms, all applicable laws and regulations, and the terms of any third-party services integrated into the App.
5.2 Prohibited Uses
You agree that you will not use the App to violate any law or regulation, infringe on the intellectual property rights of any person, transmit any harmful, unlawful, or objectionable content, or attempt to interfere with the App's functionality or security.
5.3 Aviation and Safety Decisions
You acknowledge that density altitude calculations provided by the App are approximations for informational purposes only. You are solely responsible for verifying all data through independent, certified sources and for ensuring that any aviation or safety-related decision is made using official and certified reference materials. Do not use this App as a primary basis for any decision where an error could cause injury or damage. See the separate Disclaimer for full details on the App's limitations.
5.4 Data Backup
The App stores your Data Log entries locally on your device. You are solely responsible for backing up any data you wish to preserve. We are not liable for the loss of any data stored within the App due to device failure, accidental deletion, App deletion, iOS updates, or any other cause.
THE APP IS PROVIDED "AS-IS" AND "AS AVAILABLE," WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED. TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, WE EXPRESSLY DISCLAIM ALL WARRANTIES, INCLUDING BUT NOT LIMITED TO IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, ACCURACY, AND NON-INFRINGEMENT.
We do not warrant that the App will be uninterrupted, error-free, or free of viruses or other harmful components. We do not warrant the accuracy, completeness, or timeliness of any data provided by the App, including GPS location data, elevation data from USGS, or weather data from Apple WeatherKit.
This App is not suitable for aviation operational decisions, medical decisions, financial decisions, or any other safety-critical application. See the Disclaimer for further detail.
TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, JAMES WATTS SHALL NOT BE LIABLE FOR ANY INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL, EXEMPLARY, OR PUNITIVE DAMAGES ARISING OUT OF OR RELATED TO YOUR USE OF OR INABILITY TO USE THE APP, INCLUDING BUT NOT LIMITED TO LOSS OF DATA, PERSONAL INJURY, DEATH, PROPERTY DAMAGE, LOSS OF REVENUE, OR LOSS OF BUSINESS — EVEN IF WE HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
If we are found liable under any theory of law, our total cumulative liability to you shall not exceed the amount you actually paid for the App through the Apple App Store.
By using the App, you assume all risk associated with your reliance on the App's calculations, data, and features. This limitation of liability is a fundamental element of the basis of the bargain between us.
We do not directly process refunds. All refund requests must be submitted through Apple. Apple generally allows refund requests within 14 days of purchase for qualifying reasons, including app defects or unauthorized purchases.
To request a refund through Apple:
Apple's refund decisions are final and at their sole discretion. If the App functions as described, Apple may deny a refund request.
The App integrates with the following third-party services. Your use of these services is subject to their respective terms and policies, which we encourage you to review. We are not responsible for the availability, accuracy, or conduct of these services.
We reserve the right to update or modify these Terms at any time. When we do, we will update the "Last Updated" date at the top of this document. We may also notify you of material changes through an App update or within the App itself. Your continued use of the App after any changes are posted constitutes your acceptance of the revised Terms. We recommend reviewing these Terms periodically.
11.1 Termination by Developer
We may suspend or terminate your license to use the App at any time, without notice, if you violate these Terms, attempt to reverse engineer or exploit the App, use the App for illegal purposes, or violate the terms of any integrated third-party service.
11.2 Effect of Termination
Upon termination, your license to use the App is immediately revoked. You must cease all use of the App and delete it from your devices. Termination does not entitle you to a refund. Sections of these Terms that by their nature should survive termination — including intellectual property rights, disclaimer of warranties, limitation of liability, and governing law — will continue to apply.
11.3 Termination by User
You may terminate this agreement at any time by deleting the App from all of your devices.
These Terms are governed by and construed in accordance with the laws of the United States, without regard to its conflict of law provisions. Any dispute arising from or related to these Terms or the App shall be resolved through good-faith negotiation. If negotiation fails, disputes shall be subject to binding arbitration or resolution in a court of competent jurisdiction, consistent with applicable law.
To the extent Apple's App Store terms require a different governing jurisdiction or dispute resolution mechanism, Apple's terms shall prevail.
If you have questions about these Terms of Service, please contact: Support@QuickDA.app
By downloading and using Quick DA, you acknowledge that you have read these Terms of Service in their entirety, that you understand them, and that you agree to be bound by them. You also acknowledge that you have read and understood the Disclaimer and Privacy Policy, which form part of this agreement.
This Privacy Policy describes how Quick DA (the "App"), developed by James Watts ("we," "us," or "our"), handles your information. We are committed to being transparent about our data practices. Please read this policy carefully.
Quick DA is a density altitude calculator. To function, the App requests access to your device's location and fetches weather and elevation data from third-party services on your behalf. We do not operate servers, do not create user accounts, and do not collect or transmit any personal information to our own systems.
With your explicit permission, the App accesses your device's GPS to determine your current location. Location data is used solely within the App to:
Your location is processed on-device and passed directly to Apple WeatherKit and USGS APIs in the form of latitude/longitude coordinates. We do not store, log, or transmit your location to any server we operate.
On supported devices, the App may read the device's built-in barometric pressure sensor. This data is processed entirely on-device and is never transmitted externally.
If you choose to save a calculation to the Data Log, that entry — including your input values, calculated density altitude, timestamp, and optional location name — is stored locally on your device using Apple's on-device storage. This data never leaves your device unless you explicitly export or share it.
We do not collect, store, or process:
The App integrates with the following third-party services. When these services are used, your data is subject to their respective privacy policies.
4.1 Apple WeatherKit
The App requests weather data — including temperature, dew point, and barometric pressure — from Apple WeatherKit using your device's location coordinates. Apple WeatherKit is governed by Apple's Privacy Policy and WeatherKit Terms of Use. We do not receive or store the weather data Apple returns beyond the current app session.
4.2 USGS Elevation API
The App queries the U.S. Geological Survey's public elevation API using your device's GPS coordinates to retrieve terrain elevation. The USGS API is a free public service operated by the U.S. federal government. We do not store elevation responses beyond the current app session.
4.3 Apple App Store
Your purchase of the App is processed by Apple through the App Store. Apple collects payment and account information in accordance with their own privacy policy. We receive no payment or personal information from Apple as part of this transaction.
If you have opted in to sharing analytics with app developers through your iOS privacy settings, Apple may automatically share anonymized crash reports and basic usage diagnostics with us through App Store Connect. This data is aggregated and anonymized by Apple before we receive it and cannot be used to identify you individually. You can control this setting in Settings → Privacy & Security → Analytics & Improvements on your iOS device.
Quick DA is not directed at children under the age of 13. We do not knowingly collect any personal information from children. If you believe a child has provided personal information through the App, please contact us and we will take appropriate steps to address it.
All data stored by the App — including your Data Log entries and preferences — is stored locally on your device. You can delete this data at any time by:
We have no ability to remotely delete or access your on-device data.
Depending on your jurisdiction, you may have rights regarding your personal data including the right to access, correct, or delete it. Because we do not collect or store personal information on our own servers, most of these rights are exercised directly through your iOS device settings or by deleting the App. If you have privacy-related questions or concerns, please contact us.
We may update this Privacy Policy from time to time. When we do, we will update the "Last Updated" date at the top of this document. We encourage you to review this policy periodically. Continued use of the App following any changes constitutes your acceptance of the updated policy.
If you have questions about this privacy policy, please contact: Support@QuickDA.app