Terms of Service
Last updated: July 29, 2026
Last updated: July 29, 2026
By downloading, installing, or using the Device Optical Aid (DOA) desktop application or visiting the DOA website at deviceopticalaid.com ("the Service"), you agree to be bound by these Terms of Service ("Terms") and our Privacy Policy, which is incorporated herein by reference.
If you do not agree to these Terms in their entirety, you must not install or use the application or access the website. Your continued use of the Service following any update to these Terms constitutes acceptance of the revised Terms.
These Terms apply to the Windows desktop application and any future platform releases (macOS, Linux). DOA is operated by Cedric Julien .E, an individual operator based in Douala, Cameroon.
DOA is not a medical device. It is not regulated, certified, or approved as a medical device by any health authority including the FDA, CE, or any equivalent body. It is not a substitute for prescription eyewear, contact lenses, corrective surgery, or professional eye care of any kind.
The visual corrections applied by DOA are computational approximations based on user-entered prescription values. They are not clinically validated, optometrically certified, or equivalent to wearing professionally prescribed corrective lenses. Individual results will vary based on prescription accuracy, screen type, viewing distance, lighting, and individual physiology.
Stop using DOA immediately and consult a qualified eye care professional if you experience any of the following:
Regular comprehensive eye examinations remain necessary regardless of DOA usage. DOA does not replace and is not intended to delay any eye care treatment, examination, or professional consultation.
DOA alters the appearance of your display in real time, including through color adjustment filters. Some users may notice the corrected image looks unfamiliar at first and becomes more comfortable over several days as the visual system adapts. This is a normal perceptual effect and not a change to your eyesight. If you have photosensitive epilepsy or any condition triggered by changes in visual contrast, color, or motion, consult a medical professional before use and discontinue use if you experience any adverse reaction.
By using DOA, you expressly acknowledge that you understand and accept these limitations and assume full personal responsibility for any effects, physical, visual, or otherwise, that you attribute to use of the application.
DOA is a desktop application that applies real-time visual correction to your screen. It is designed for users with refractive errors who want clearer screen readability in situations where they are not wearing glasses. The application provides:
DOA is provided as a convenience tool for screen use only. It is not designed for, and should not be used as a substitute for, corrective eyewear in any context outside of screen-based activity.
You acknowledge and agree that:
If you have any existing eye condition, recent eye surgery, or have been advised by a medical professional to limit screen exposure, you must consult your eye care provider before using DOA.
To apply vision correction, DOA captures your screen in real time using the Windows Graphics Capture API. By using the application you acknowledge and consent to this local screen processing. You should be aware that:
Certain features require a DOA account. By registering you agree to:
One account may be used across a reasonable number of personal devices belonging to the same individual. Account sharing across multiple users or household members is not permitted under a single subscription.
We reserve the right to require you to update your information or to suspend accounts with inaccurate or outdated details.
The free tier of DOA is subject to the following technical restrictions:
Attempting to circumvent these limits, including by manipulating local storage, system clocks, network traffic, application files, or by using multiple accounts, constitutes a material breach of these Terms and may result in immediate account suspension without refund.
Premium removes all free tier restrictions and unlocks unlimited daily usage, unlimited saved prescriptions, multi-monitor support, the full visual filters suite, watermark removal, and priority support.
Subscriptions are billed monthly ($4.99/month) or annually ($39.99/year) and renew automatically unless cancelled before the renewal date. All payments are processed by Creem, who acts as Merchant of Record for all transactions. Creem handles tax compliance, chargebacks, and payment disputes. You may see "Creem" on your bank or card statement. DOA never stores, accesses, or processes your payment card details or billing information.
We may change subscription prices. Any change is announced at least 30 days in advance by email to your registered address and takes effect only at your next renewal, never mid-period. If you do not accept a new price you may cancel before it takes effect and you will not be charged the new amount. Continuing past the effective date constitutes acceptance of the new price.
You may cancel your subscription at any time through the app or by contacting support. Cancellations take effect at the end of the current billing period, and you retain Premium access until the period expires. No partial-period refunds are issued for mid-cycle cancellations except where required by applicable law.
If you are an EU or EEA consumer, you have a statutory right of withdrawal of 14 days from the date of purchase. However, by initiating use of the Premium service before the 14-day period expires, you expressly consent to the service beginning immediately and acknowledge that your right of withdrawal is waived upon first use of the Premium features. If you have not used Premium features, you may exercise your right of withdrawal by contacting us at support@deviceopticalaid.com within 14 days of purchase.
Early access coupon holders: Free Premium codes issued during the beta period do not auto-renew into paid subscriptions when they expire. You will be moved to the free tier automatically unless you actively choose to subscribe.
We want every user to have a positive experience. If you are not satisfied, contact us within 14 days of purchase at support@deviceopticalaid.com.
Refund requests are reviewed individually. Approved refunds are credited to the original payment method within 5–10 business days depending on your bank or card provider.
We reserve the right to decline refund requests where the subscription has been substantially used, where refund abuse is suspected, or where a prior refund has already been granted for the same account.
Refunds do not affect any obligations you have under these Terms, and a refund does not constitute acknowledgment of any fault or liability on DOA's part.
EU and EEA consumers retain all statutory refund rights under applicable consumer law, which take precedence over this policy where they conflict.
You agree not to use DOA or the DOA website to:
The DOA application, its source code, correction algorithms, branding, design, website content, and all related materials are the intellectual property of Device Optical Aid, operated by Cedric Julien .E, and are protected by applicable copyright, trade secret, and intellectual property laws.
You are granted a limited, personal, non-exclusive, non-transferable, non-sublicensable license to install and use the application on your personal device(s) for personal, non-commercial purposes only, subject to these Terms. This license does not grant you any ownership rights, rights to the underlying technology, or rights to use the DOA brand or trademarks.
Any feedback, suggestions, or ideas you submit to us may be used by DOA without restriction or compensation to you. You waive any moral rights in such submissions to the maximum extent permitted by law.
DOA uses technical and cryptographic measures to protect its licensing, usage enforcement, and application integrity. These include but are not limited to usage timers, subscription verification via Firebase token authentication, ASAR integrity validation, and native addon version verification.
Attempting to tamper with, patch, modify, or disable any of these mechanisms is strictly prohibited and constitutes a material breach of these Terms. Accounts found engaging in tampering may be permanently suspended without refund and may be subject to legal action under applicable computer fraud and software protection laws.
To the maximum extent permitted by applicable law, DOA, its operator (Cedric Julien .E), and any associated parties shall not be liable for any of the following arising from or related to your use of or inability to use the application:
Our total cumulative liability for any claim arising under these Terms, regardless of the nature of the claim, shall not exceed the total amount you paid to DOA in the twelve (12) months immediately preceding the event giving rise to the claim, or USD $10.00, whichever is greater.
Some jurisdictions do not allow the exclusion or limitation of certain warranties or liabilities. In such jurisdictions, our liability is limited to the maximum extent permitted by law. Nothing in these Terms limits liability for death or personal injury caused by gross negligence, fraud, or any other liability that cannot be excluded by law.
DOA is provided "as is" and "as available" without warranties of any kind, whether express, implied, or statutory. To the maximum extent permitted by applicable law, we expressly disclaim all warranties including but not limited to:
GPU compatibility, driver versions, display technology, operating system configuration, and individual physiological factors may all affect correction quality and application performance. DOA does not guarantee consistent results across all hardware configurations.
You agree to indemnify, defend, and hold harmless DOA, its operator (Cedric Julien .E), and any associated parties from and against any claims, damages, losses, liabilities, costs, and expenses (including reasonable legal fees) arising from or related to:
Your use of DOA is also governed by our Privacy Policy, which is incorporated into these Terms by reference. The Privacy Policy explains in detail what data we collect, how it is used, your rights regarding it, and our compliance with GDPR, CCPA, and other applicable data protection regulations.
We reserve the right to suspend or terminate your access to DOA at any time at our discretion, including for violations of these Terms, fraudulent activity, attempted circumvention of technical protections, or abuse of the refund policy. Where reasonably practical, we will provide notice before termination.
You may terminate your account at any time by contacting support or using the account deletion option within the application. Upon termination, your personal data will be deleted in accordance with our Privacy Policy. Termination does not entitle you to a refund except as described in Section 09.
Sections 02, 04, 11, 13, 14, 15, and 19 of these Terms survive termination.
We may update these Terms as the product, legal landscape, or operating context evolves. When we make significant changes, registered users will be notified by email at least 14 days before the changes take effect. The "Last Updated" date at the top of this page always reflects the most recent revision.
Continued use of DOA after the effective date of updated Terms constitutes your acceptance of the changes. If you do not agree to updated Terms, you must stop using the application and delete your account before they take effect.
These Terms are governed by the laws applicable in Cameroon, without regard to conflict of law provisions. This choice of governing law does not deprive you of any mandatory consumer protections available under the laws of your country of residence.
For EU and EEA consumers: Nothing in these Terms limits your rights under applicable EU consumer protection law. EU law applies where it provides stronger protections than Cameroonian law. You may also have the right to refer disputes to your local consumer protection authority or alternative dispute resolution body.
For California consumers: Nothing in these Terms limits your rights under the CCPA or other applicable California consumer law.
Any dispute arising from these Terms shall first be addressed through good-faith direct negotiation. Either party may initiate dispute resolution by providing written notice to the other. If a dispute cannot be resolved within 30 days of such notice, either party may pursue available legal remedies.
DOA is designed and operated in compliance with applicable laws and regulations, including but not limited to the EU General Data Protection Regulation (GDPR), the California Consumer Privacy Act (CCPA), and applicable consumer protection law in jurisdictions where DOA is made available.
DOA is not classified as a medical device under EU Regulation 2017/745 (MDR), FDA regulations, or equivalent regulations in other jurisdictions, and is not subject to regulatory approval processes applicable to medical devices. Users in jurisdictions with specific regulations regarding vision-assistance software are responsible for verifying compliance with their local laws before use.
DOA is intended for adults. You must be at least 18 years old, or the age of legal majority where you live, to create an account or buy a subscription. By registering you confirm that you meet this requirement and have the legal capacity to enter a binding agreement.
Where local law allows use by a minor aged 16 or over with the consent of a parent or legal guardian, that consent must be given before an account is created. The parent or guardian accepts these Terms on the minor's behalf and is responsible for any charges incurred.
We do not knowingly allow anyone under 13 to hold an account. If we learn that an account belongs to a child under 13, we will close it and delete the associated data.
Separately from account eligibility, DOA is not designed for children, whose vision is still developing. Consult an eye care professional before allowing a minor to use any display correction tool.
DOA is currently offered as beta software. It is under active development and you should expect it to behave less predictably than finished software.
Beta status does not reduce your statutory rights as a consumer and does not excuse us from the refund obligations in these Terms. It does mean that an expectation of uninterrupted or defect-free operation is not reasonable while the product carries the beta label.
If you have paid for Premium and a defect materially prevents you from using it, contact support@deviceopticalaid.com and we will put it right, including by refund where appropriate.
We do not guarantee uninterrupted availability. Access may be suspended for maintenance, updates, technical failure, or reasons outside our control, and parts of the service depend on third parties whose availability we do not control.
We may modify, limit, or discontinue any feature, tier, or the service as a whole. Where a change materially reduces functionality you are actively paying for, we will give at least 30 days' notice by email, and you may cancel and receive a pro-rata refund for the unused part of your billing period.
If DOA is discontinued entirely, we will give reasonable advance notice, stop accepting new subscriptions, and provide a way to export your saved prescription values before access ends.
DOA depends on third-party providers for payments, authentication, email delivery, and hosting. Your use of those services is governed by their own terms and privacy policies, and we are not responsible for their acts, omissions, outages, or pricing.
Our website links to external sites, including research publications and support resources. Those links are provided for reference. We do not control, endorse, or accept responsibility for the content, accuracy, or privacy practices of any external site.
You may not use, download, or export DOA in breach of any applicable export control or sanctions law. You confirm that you are not located in, and are not a national of or ordinarily resident in, any country or territory subject to comprehensive trade sanctions, and that you do not appear on any restricted or denied-party list maintained by a competent authority.
We may suspend or refuse service where providing it would breach applicable sanctions or export restrictions.
We are not liable for any failure or delay in performing our obligations where it results from causes beyond our reasonable control. These include internet or hosting outages, failures of payment processors or authentication providers, power or telecommunications failures, cyberattacks, natural disasters, epidemics, armed conflict, civil unrest, strikes, and acts of government or regulatory authorities.
If such an event prevents us from providing paid service for a prolonged period, you may cancel and request a pro-rata refund for the affected part of your subscription.
You may not assign or transfer these Terms, your account, or any rights under them without our prior written consent. Any attempted transfer without consent is void.
We may assign these Terms, in whole or in part, to a successor in a merger, acquisition, restructuring, or sale of assets relating to DOA. Where such a transfer involves your personal data, we will notify you in advance and you may delete your account before the transfer takes effect.
We send account, billing, security, and legal notices by email to the address registered on your account, and where relevant by notice inside the application. Keep that address current and monitored. Notices are treated as received 24 hours after sending unless we receive a delivery failure.
You may send notices to us at support@deviceopticalaid.com. You consent to receiving communications electronically and agree that electronic notices satisfy any legal requirement that a communication be in writing.
Service and security messages are not marketing and cannot be opted out of while you hold an account. Optional product announcements can be declined without affecting your access.
Termination or expiry of your account does not end the provisions that by their nature should continue. The Medical & Health Disclaimer, Assumption of Risk, Intellectual Property, Anti-Tampering & Integrity, Limitation of Liability, Disclaimer of Warranties, Indemnification, Governing Law & Dispute Resolution, Export Controls & Sanctions, Survival, and Severability & Entire Agreement provisions survive, together with any payment obligations accrued before termination.
If any provision of these Terms is found to be unenforceable or invalid under applicable law, that provision will be limited or eliminated to the minimum extent necessary, and the remaining provisions will continue in full force and effect.
These Terms, together with our Privacy Policy, constitute the entire agreement between you and DOA regarding use of the Service and supersede all prior agreements, representations, or understandings of any kind.
Our failure to enforce any provision of these Terms shall not constitute a waiver of our right to enforce that provision in the future.
For questions about these Terms, legal notices, or compliance inquiries:
For data and privacy questions specifically, see our Privacy Policy.
By installing and using DOA, you confirm that you have read and understood these Terms of Service and our Privacy Policy, that you are at least 13 years of age (or 16 in the EU), that you are legally capable of entering into a binding agreement, and that you agree to be bound by these Terms. If you do not agree, please uninstall the application and do not use the Service.