Terms of use

Who you are contracting with

Lumavik is operated by Vast Flow, LLP. References to "we", "us" and "our" mean Vast Flow, LLP. References to "the app" mean the Lumavik mobile application, and "the site" means lumavik.org including the free tools published on it.

What we provide

The app and the site present space-weather information derived from public data published by the NOAA Space Weather Prediction Center, together with calculations built on that data and on standard geophysical and astronomical models. We provide this as an informational service. We are not a scientific authority, we do not produce the underlying measurements, and we are not affiliated with NOAA or with any government agency.

Forecasts are probabilities, not promises

This is the most important clause on the page and we would rather state it in plain language than bury it. Every number the app or the site shows is an estimate. Aurora visibility depends on geomagnetic activity, your latitude, darkness and cloud cover, and the last of those is outside the scope of any geomagnetic model. A high score is not a guarantee that you will see anything, and a low score is not a guarantee that you will not. We do not accept liability for travel, accommodation, time or any other cost incurred in reliance on a forecast.

Data feeds can also fail. NOAA services go down, networks drop, and a device can be offline. Where we know a value is stale or unavailable we say so rather than showing an old number as current, but we cannot guarantee uninterrupted availability of anything on this site or in the app.

Going outside is your decision

Aurora viewing frequently involves darkness, cold, remote locations, ice and driving at night. You are responsible for your own safety and for the decisions you make about where and when to go. Nothing in the app or on the site is advice about whether a journey is safe, and we accept no liability for it. Check local conditions, tell somebody where you are going, and do not rely on a phone as your only light or navigation.

Free tools on this site

The calculators on lumavik.org are provided free and without warranty. They use standard approximations — the tilted-dipole model for geomagnetic coordinates and a low-precision solar position series for twilight times — which are stated on the pages themselves. They are suitable for planning and not for any application requiring survey-grade accuracy. Inputs you type stay in your browser; we neither receive nor store them.

Subscriptions and billing

The core forecast is free. A Pro subscription is available at $2.99 weekly or $19.99 yearly, with a 7-day free trial on the yearly plan. Prices shown in the app are set in App Store Connect and are authoritative; prices quoted on this website are for information and may lag a change or differ by region and currency.

All subscriptions are sold and processed by Apple through the App Store. Payment is charged to your Apple account at confirmation of purchase. Subscriptions renew automatically unless auto-renew is turned off at least 24 hours before the end of the current period, and your account is charged for renewal within 24 hours before the end of that period. If a free trial is offered and you subscribe to the same plan before the trial ends, the unused portion of the trial is forfeited, which is Apple's rule rather than ours.

Cancelling

You can cancel at any time in your Apple account settings, and cancelling during a free trial costs nothing. Cancellation takes effect at the end of the current billing period; you keep Pro features until then. We cannot cancel a subscription on your behalf because we do not control the billing relationship. Step-by-step instructions are on the contact page.

Refunds

Refunds are handled by Apple under their own policy, and requests go through Apple rather than through us. If you believe you were charged in error, contact us as well — we cannot issue the refund, but we can support your request to Apple and we will.

Acceptable use

Use the app and the site for their intended purpose. Do not attempt to disrupt them, do not scrape the site at a volume that degrades it for other people, and do not redistribute the tools as your own product. You may quote and link to anything we publish, and we would rather you did that than paraphrase us inaccurately; a link back is appreciated. NOAA's underlying data is public domain and you do not need our permission to use it — go to the source.

Intellectual property

The app, the site design, the written articles and the calculators are our intellectual property, excluding the public-domain data they present. Third-party names and trademarks that appear on this site, including the names of other apps on the comparison pages, belong to their respective owners and are used descriptively for the purposes of comparison and commentary. Their appearance does not imply any affiliation with or endorsement by those owners.

Accuracy and corrections

We try to be accurate and we will be wrong sometimes. If you find an error in an article, a calculator or a comparison page, write to [email protected]. We correct mistakes and we say that we have, rather than editing silently.

Limitation of liability

To the fullest extent permitted by law, we are not liable for indirect or consequential loss arising from your use of the app or the site, including wasted travel and accommodation costs, missed opportunities and loss of data. Where liability cannot be excluded by law, it is limited to the amount you have paid us in the twelve months before the claim, which for most users is zero because the core product is free. Nothing here limits liability for death or personal injury caused by negligence, or for fraud, where such limitation is not permitted.

Changes

We may update these terms as the product changes. The date at the top shows when they were last revised. Continuing to use the app or the site after a change means you accept the revised terms. Material changes affecting subscriptions will be announced in the app.

Termination

You can stop using the app at any time by deleting it. We may suspend access if the acceptable-use terms above are breached in a way that harms the service or other users. Ending your use does not entitle you to a refund of a period already paid for, which remains subject to Apple's policy.

Feedback

If you send us a suggestion, a bug report or an idea for a feature, we may act on it without owing you compensation or attribution, and you grant us the right to do so. This is not us claiming your work — it exists because a large share of good ideas arrive from users, several of them independently, and we cannot run a product where implementing an obvious improvement creates a claim. If you want to send us something you consider confidential or proprietary, say so before you send it and we will tell you whether we can accept it.

Availability and changes to the service

We may change, suspend or discontinue any part of the app or the site, including individual features and individual free tools. If we discontinue a paid feature during a subscription period we will say so in the app, and Apple's refund process remains open to you. We do not guarantee that a specific free tool on this website will exist indefinitely, although we have no plan to remove any of them, and we will not put an existing free tool behind a paywall.

Third-party services

The app and the site depend on services we do not control, including Apple for distribution and billing, NOAA for data, and advertising and analytics providers named in the privacy policy. Their own terms apply to their own services, and an outage or a change on their side can affect what we can deliver. We are not responsible for the content or practices of any third-party site we link to, including the App Store listings referenced on the comparison pages.

Severability and waiver

If any provision of these terms is found unenforceable, that provision is limited or removed to the minimum extent necessary and the rest remains in force. If we do not enforce a provision on one occasion, that is not a waiver of the right to enforce it later.

Assignment and entire agreement

You may not transfer your rights under these terms without our consent. We may assign them as part of a merger, acquisition or sale of assets, on notice. Together with the privacy policy, these terms are the entire agreement between you and us concerning the app and the site, and they replace any earlier version.

Governing law

These terms are governed by the laws applicable to Vast Flow, LLP's place of establishment. If you are a consumer, this does not deprive you of the protection afforded by the mandatory consumer law of your country of residence.

Contact

Anything about these terms goes to [email protected]. We read every message.