Terms and Conditions of Use

1Acceptance of the terms

These Terms and Conditions of Use (the “Terms”) are a legal agreement between you (the “user”) and Jorge Maldonado Borbón, trading under the brand IndieLob (the “developer”), covering the use of the Vuelto mobile app (the “app”).

By downloading, installing, opening or using Vuelto you accept these Terms in full. If you disagree with any part of them, do not use the app and uninstall it.

If you use the app while under the age of majority, you must do so with the consent and under the supervision of your parent or legal guardian, who accepts these Terms on your behalf.

2Who provides the service

• Owner and developer: Jorge Maldonado Borbón, trading under the brand IndieLob.
• App: Vuelto, for iPhone and iPad, distributed exclusively through Apple’s App Store.
• Contact: support@indielob.com

Vuelto is an independent product. It is not affiliated with, sponsored by or endorsed by Apple Inc. or by any other company mentioned in the app.

3What Vuelto is

Vuelto is a formula calculator for iPhone and iPad that runs entirely on your device. Among other features, it includes:

• A library of 225 built-in formulas, organised into categories: mathematics, statistics, geometry, physics, finance, accounting, everyday life, health, engineering, chemistry and conversions.
• A builder for your own formulas, with an editor for expressions, variables and symbols.
• A change calculation formula with configurable bill and coin denominations.
• An optional voice mode for dictating formulas and values, with an optional spoken assistant.
• A local history of the calculations you save.
• iCloud syncing of your own formulas and favourites, at no cost.
• An interface in ten languages and actions for Siri and Shortcuts.

The app requires iOS or iPadOS 18 or later. Some features depend on the device having a microphone, speech recognition, or a signed-in iCloud account.

4Licence to use

The developer grants you a personal, limited, non-exclusive, non-transferable and revocable licence to install and use Vuelto on the Apple devices you own or control, in accordance with Apple’s App Store Usage Rules, for your own personal or professional purposes.

The app is licensed to you, not sold. Unless these Terms state otherwise, Apple’s Standard End User Licence Agreement for licensed applications applies by default. In the event of a conflict between the two texts, these Terms prevail to the extent they are compatible with Apple’s rules.

5Free version and Vuelto Pro

Vuelto is free to download and can be used indefinitely without paying. Vuelto Pro is an optional in-app purchase that unlocks the full content.

Vuelto Pro is a one-time purchase (a non-consumable): it is not a subscription, it does not renew and it produces no recurring charges. It is tied to the Apple Account used to buy it. It is not currently enabled for Family Sharing, so it is not shared with other members of a family group.

The developer reserves the right to adjust, in future versions, exactly which content forms part of the free portion, always without removing features from anyone who has already bought Vuelto Pro.

6Payments, refunds and restoring

• Payment is taken by Apple through your Apple Account. The final price and any applicable taxes are those shown by the App Store in your country at the time of purchase.
• The developer does not process payments and has no access to your bank or card details.
• Refunds are handled exclusively by Apple under its own policies. Requests are made at reportaproblem.apple.com; the developer cannot grant, refuse or process refunds.
• If you change device or reinstall the app, use “Restore purchase” in Settings to recover Vuelto Pro with the same Apple Account. The purchase cannot be recovered with an Apple Account other than the one that made it.
• Access to Vuelto Pro depends on Apple confirming the purchase. If Apple reverses or cancels a transaction, access may be switched off.

7Responsible use of the results

• Always verify results before making decisions involving money, safety, health, legal obligations or material consequences. A mistyped figure, a wrong unit or a badly chosen formula produces a wrong result.
• The built-in formulas are selected and reviewed with care, but the developer does not warrant that they are free of errors, that they apply to your particular case, or that they comply with the tax, accounting, health or technical rules in force in your country.
• The formulas you create are your sole responsibility: the app evaluates the expression you write; it does not judge whether it is correct or fit for your purpose.
• Voice mode depends on the system’s speech recognition and may misread a word or a figure. Check the captured values on screen before relying on a result.
• Calculations use the device’s standard floating-point arithmetic, with the rounding that entails; it is not a substitute for certified invoicing, accounting or metrology systems.
• For matters that call for it, consult a qualified professional.

8Your content and your data

• The formulas you create, your favourites and your calculation history are yours. The developer claims no rights over them and cannot access them: they live on your device and, in the case of formulas and favourites, in your private iCloud.
• You are responsible for the content you write into your formulas (names, descriptions and expressions). Do not put sensitive or confidential information into them that you would not want kept on your device.
• Make your own backups. The developer keeps no copies and therefore cannot recover data lost through accidental deletion, device failure, uninstalling the app, or iCloud service incidents.
• Calculation history never syncs: if you change device, it does not travel with you.

9Voice mode and permissions

Voice mode requires you to grant the microphone and speech recognition permissions iOS requests. They are optional: you can use the whole app without them and revoke them at any time in Settings › Vuelto.

Transcription is carried out by Apple’s operating system, which depending on the device and language may process it on the device itself or on Apple’s servers. The developer does not record, store or receive your voice. The details are in the Privacy Policy.

Use voice mode sensibly: do not use it while driving or in situations that demand your attention, and bear in mind that the spoken assistant may be audible even when the ring switch is set to silent.

10Prohibited uses

In using Vuelto, you undertake not to:

• Decompile, disassemble, reverse engineer or attempt to extract the source code of the app, except to the extent applicable law expressly permits.
• Copy, modify, translate, sell, rent, sublicense or redistribute the app or its content, including its formula library.
• Circumvent, disable or tamper with the purchase and verification mechanisms of Vuelto Pro.
• Use the app for unlawful or fraudulent purposes, or to infringe the rights of others.
• Use the app in an automated or abusive way that interferes with its normal operation.
• Remove or alter intellectual property notices, trade marks or logos.

11Intellectual property

The app, its code, its design and interface, its texts, its icons, the name Vuelto, the IndieLob brand, its logos and the selection, wording and organisation of its formula catalogue are the property of Jorge Maldonado Borbón and are protected by intellectual and industrial property law.

Mathematical, physical or financial formulas in the public domain are not, in themselves, anyone’s property; what is protected is their selection, adaptation, wording, translation and presentation within the app.

These Terms transfer no ownership rights in the app to you beyond the licence described in section 4.

12Privacy

How information is handled is described in the Privacy Policy, which forms an integral part of these Terms. In short: Vuelto collects no personal data, uses no analytics or advertising, and sends none of your information to developer servers.

13Availability and changes to the app

• The developer may update, modify, add or withdraw features and formulas, and release new versions that fix bugs or improve performance.
• Updating the app or the operating system may be necessary for it to keep working correctly. Older versions may stop being supported.
• The developer may stop distributing or discontinue the app. In that case, the copy you already have installed will keep working for as long as your device allows, but it may receive no further updates.
• Features such as iCloud syncing, speech recognition, Siri and purchases depend on Apple services and on your connection; their interruptions or changes are outside the developer’s control.
• Support is provided, so far as is reasonable, through the contact email. Apple has no obligation whatsoever to furnish support for the app.

14Disclaimer of warranties

The app is provided “as is” and “as available”. To the fullest extent permitted by applicable law, the developer disclaims all express or implied warranties, including those of merchantability, fitness for a particular purpose, accuracy of results and non-infringement.

The developer does not warrant that the app will run uninterrupted or error-free, that it will be compatible with every device and configuration, or that its calculations are suitable for professional, regulated or certified use.

Some jurisdictions do not allow certain warranties to be excluded, so some of these exclusions may not apply to you. Nothing in these Terms limits the consumer rights granted to you on a mandatory basis.

15Limitation of liability

To the fullest extent permitted by law, the developer shall not be liable for indirect, incidental, special, punitive or consequential damages, nor for loss of profits, revenue, data, formulas or business opportunities arising from the use of, or inability to use, Vuelto.

In particular, and without limiting the foregoing, the developer is not liable for the decisions you make or the harm you suffer as a result of a result obtained with the app, including calculation errors, mistyped values, wrong units, incorrect voice-mode transcriptions or badly defined custom formulas.

The developer’s total aggregate liability for any claim relating to the app is limited to the amount you actually paid for Vuelto Pro in the twelve months preceding the event giving rise to the claim or, if you made no purchase, to zero.

These limitations do not exclude liability that cannot lawfully be excluded, such as wilful misconduct or personal injury caused by gross negligence.

16Apple-related terms

These Terms are entered into between you and the developer, not with Apple Inc. Accordingly:

• Apple is not responsible for the app or its content, and has no obligation to furnish any maintenance or support services with respect to it.
• If the app fails to conform to any applicable warranty, you may notify Apple, and Apple may refund the purchase price if appropriate. Beyond that, and to the maximum extent permitted by law, Apple will have no other warranty obligation.
• The developer, and not Apple, is responsible for addressing claims relating to the app: product liability, failure to conform to legal requirements, and consumer protection or data protection claims.
• The developer, and not Apple, is responsible for investigating and resolving any third-party intellectual property infringement claim relating to the app.
• You represent that you are not located in a country subject to a U.S. Government embargo and that you are not listed on any restricted-party list, in accordance with applicable export control laws.
• Apple and its subsidiaries are third-party beneficiaries of these Terms and, upon your acceptance, Apple will have the right to enforce them against you.

17Termination

You may end these Terms at any time by uninstalling the app. The developer may suspend or revoke the licence if you materially breach these Terms, in particular section 10.

On termination of the licence you must stop using the app and remove it from your devices. The sections on intellectual property, disclaimer of warranties, limitation of liability and governing law survive termination.

18Governing law and dispute resolution

These Terms are governed by the laws of the United Mexican States and, where applicable, by those of the State of Durango, excluding their conflict-of-law rules. For any dispute, the parties expressly submit to the competent courts of the city of Durango, Durango, Mexico, without prejudice to the mandatory consumer rights granted to you in your place of habitual residence, including the ability to bring proceedings before the courts of your domicile.

If any clause of these Terms is held void or unenforceable, the remainder shall continue in full force.

19Changes to these terms

The developer may update these Terms to reflect changes to the app or to applicable law. The version in force will always be the one published on this page, with its date of entry into force. If a change is substantial, notice will be given in the app itself or in the App Store release notes. Continuing to use Vuelto after they take effect constitutes acceptance of the updated Terms; if you do not accept them, uninstall the app.

20Language and prevailing version

The Spanish version of these Terms and Conditions of Use is the only official and legally binding version. The versions available in other languages — English, French, Italian, Brazilian Portuguese, European Portuguese, German, Turkish, Simplified Chinese and Dutch — are published for information and convenience only, to aid understanding, and have no legal force in themselves.

In the event of any discrepancy, contradiction, ambiguity, translation error or omission, or conflict of interpretation between the Spanish version and any of its translations, the Spanish version shall always prevail in full and shall govern for all legal purposes. You can read it here: Términos y Condiciones de Uso (español).

21Contact

For questions, support or legal matters regarding these Terms: