Last Updated: September 19, 2026
These Terms of Service ("Terms") are a legal agreement between you and Laitei ("we," "us," or "our") governing your use of the Equation Solver Android application (package name com.equationsolver.laitei), available on Google Play (the "App"). By downloading, installing, or using the App, you agree to be bound by these Terms. If you do not agree, please do not use the App.
Equation Solver helps you solve mathematical equations that you enter, including linear equations, quadratic equations, cubic equations, polynomial equations up to degree 30, and systems of linear equations with up to 10 unknowns. All calculations are performed entirely on your device. We do not require an account or login, and we do not process, store, or transmit the content of your equations on any server.
The App is free to download and use. The free version is supported by advertising served through Google AdMob, including a banner ad displayed within the App and periodic interstitial ads. By using the free version, you agree to the display of these ads. Details about the data AdMob may collect (such as an advertising identifier) to serve ads are described in our Privacy Policy, linked below.
We offer an optional paid upgrade, "Equation Solver Pro," purchased through Google Play Billing and managed with the help of our subscription platform provider, RevenueCat. Pro is available in the following options:
Purchasing Pro unlocks the following features:
Monthly and Yearly subscriptions automatically renew at the end of each billing period unless you cancel before the renewal date. All billing, renewal, and cancellation of subscriptions is handled entirely by Google Play — we do not have direct access to your payment information and do not process cancellations ourselves. You can review, manage, or cancel your subscription at any time through Google Play's subscription management page.
Consistent with Google Play's standard policy, we do not provide partial refunds for unused time remaining on a subscription period if you cancel partway through it. Any refund requests are subject to Google Play's own refund policies and procedures.
If we change the price of a subscription, we will provide advance notice before the new price takes effect for existing subscribers, in accordance with Google Play's requirements. Continuing your subscription after a price change takes effect constitutes acceptance of the new price.
The Lifetime option is a single, one-time purchase that is not a subscription and does not recur or auto-renew. It unlocks Pro features permanently for the Google Play account used to make the purchase, subject to these Terms and to Google Play's purchase and refund policies.
The App is provided for informational and educational purposes. While we aim for mathematical accuracy, equation results are provided "as is" and "as available," without any guarantee of correctness, completeness, or fitness for a particular purpose. You are solely responsible for independently verifying any result before relying on it — including, without limitation, for schoolwork, academic submissions, financial decisions, engineering calculations, or any other decision with real-world consequences. We are not liable for any loss, damage, grade, financial outcome, or other consequence arising from your use of, or reliance on, results produced by the App.
For certain equation types (such as those involving radicals, logarithms, or trigonometric functions), the App uses numerical methods that search for solutions within a bounded range. These methods may not find every solution that mathematically exists, particularly solutions outside the searched range or edge cases the algorithm does not cover. The absence of a result, or an incomplete set of results, does not necessarily mean no solution exists.
You agree to use the App only for lawful purposes and in accordance with these Terms. You must not:
The App, including its source code, design, graphics, icons, logos, and all related intellectual property, is owned by Laitei and is protected by copyright, trademark, and other intellectual property laws. Except for the limited right to use the App granted under these Terms, no rights, title, or interest in the App are transferred to you. All trademarks, service marks, and trade names used in the App are the property of their respective owners.
THE APP IS PROVIDED "AS IS" AND "AS AVAILABLE," WITHOUT WARRANTIES OF ANY KIND, WHETHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT, OR ACCURACY OF RESULTS. WE DO NOT WARRANT THAT THE APP WILL BE UNINTERRUPTED, ERROR-FREE, OR FREE OF HARMFUL COMPONENTS.
TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, WE SHALL NOT BE LIABLE FOR ANY INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL, OR PUNITIVE DAMAGES, OR ANY LOSS OF DATA, PROFITS, OR GOODWILL, ARISING OUT OF OR RELATED TO YOUR USE OF, OR INABILITY TO USE, THE APP, EVEN IF WE HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. OUR TOTAL AGGREGATE LIABILITY ARISING OUT OF OR RELATED TO THESE TERMS OR THE APP SHALL NOT EXCEED THE AMOUNT YOU PAID US, IF ANY, IN THE 12 MONTHS PRECEDING THE CLAIM. Some jurisdictions do not allow certain limitations of liability, so some of the above limitations may not apply to you.
You may stop using the App at any time by uninstalling it from your device. We reserve the right to suspend or terminate your access to the App, in whole or in part, at our discretion, if you violate these Terms or if we discontinue the App. Termination does not entitle you to a refund for any purchase already made, except as required by Google Play's own policies or applicable law. Sections of these Terms that by their nature should survive termination (including intellectual property, disclaimers, limitation of liability, and governing law) will survive.
The App is not directed at children under the age of 13, and we do not knowingly collect any personal data covered by the U.S. Children's Online Privacy Protection Act (COPPA) or similar children's privacy laws. By using the App, you represent that you meet the minimum age required in your jurisdiction to consent to these Terms, or that you have a parent or guardian's permission to do so. If you believe a child under 13 has provided us with data through the App, please contact us so we can address it.
Our Privacy Policy describes what information is collected by third-party services used in the App, including Google AdMob (for advertising) and RevenueCat (for processing purchase and subscription data), and how that information is handled. Please review our Privacy Policy at https://es.privacypolicy.laitei.dev/ for full details. It is incorporated into these Terms by reference.
We may update these Terms from time to time to reflect changes in the App, our practices, or for legal or regulatory reasons. If we make material changes, we will update the "Last Updated" date above and, where appropriate, provide additional notice (such as an in-app notice). Your continued use of the App after any changes take effect constitutes your acceptance of the revised Terms. If you do not agree to the revised Terms, you should stop using the App.
These Terms shall be governed by and construed in accordance with the laws of [Your Jurisdiction], without regard to its conflict of law principles. Any disputes arising out of or relating to these Terms or the App shall be subject to the exclusive jurisdiction of the courts located in [Your Jurisdiction], unless applicable law requires otherwise.
If you have any questions about these Terms, please contact us at [email protected].