Terms of Use
Update notice (posted October 28, 2026) We added an optional paid subscription for using Sai without ads (section 3a). Free features are unchanged. Section 3a applies to anyone who buys the subscription from the time of purchase.
1. Purpose
These terms set out the conditions for using Sai (the “Service”), the couple app provided by Neural Lab (“we”, “us”), and the rights and responsibilities of you and us.
2. Signing up
Anyone aged 14 or older (or the minimum age required in your country, if higher) can sign up with an email address, an Apple account or a Kakao account. We may restrict accounts created with someone else’s information or with false information.
3. What the Service includes
We provide a photo calendar, plans and anniversaries, diaries and comments, chat, optional period records, optional location sharing and footprints, and backup and export, free of charge. To use Sai without ads, you can choose the paid subscription in section 3a.
3a. Paid subscription (Sai Plus)
Sai Plus is an auto-renewing monthly or yearly subscription. When one of you subscribes, both people in your current couple space use Sai without ads. The price and period are shown on the purchase screen, and payment is charged to your App Store or Google Play account. The subscription renews automatically on the same terms unless you cancel at least 24 hours before the current period ends. You can cancel in your store’s subscription settings and keep the benefit until the paid period ends. Refunds follow the policy of the store you paid through and applicable law. If you disconnect, your partner loses the benefit and the subscription stays with the person who bought it. Deleting your account does not cancel a store subscription, so cancel it in the store first.
4. Couple space and sharing
You connect with one person using an invite code. Your partner can see what you post in the shared space. Period records and location are shared only to the extent you turn them on. You can disconnect at any time. We cannot recover copies your partner has already saved separately.
5. Location sharing
① When you turn on location sharing, we provide your location to your connected partner and record places you stayed together as footprints. This feature is free.
② When turning sharing on, you choose 1 hour, until the end of today, or until you turn it off, and you can stop sharing or withdraw consent at any time. When you stop, we delete your latest location.
③ As required by Korean law, we keep records of location provision (recipient and time) for 6 months, and you may ask to view them. Your location is provided only to the partner you choose, as shown on the location sharing settings screen.
④ People under 14 cannot use location sharing.
⑤ Questions and disputes about location sharing can be sent to contact@neuralab.kr.
6. Your responsibilities
Do not post other people’s photos, location or personal information without their consent, and do not use the Service to monitor, track or harass anyone. Location sharing must always be with the knowledge and consent of the person being located. Do not post content that breaks the law or infringes others’ rights. If you do, we may remove the content or restrict your use.
7. Your content
You own the photos and text you post. We use them only as needed to provide the Service (storing them, showing them to your partner, and backups).
8. Changes and interruptions
We may change features to improve the Service. If we end the Service, we will tell you 30 days in advance and let you export your records and photos during that time. The Service may pause briefly for maintenance or outages.
9. Deleting your account
You can delete your account at any time from Us → Settings → Delete account in the app, or through the account deletion page. Information after deletion is handled as described in the Privacy Policy.
10. Limitation of liability
To the extent permitted by law, we are not responsible for damage caused by events beyond our control, such as natural disasters or problems with your device or network. Period records and predicted dates are for reference only and are not medical advice or a method of contraception. Location may be delayed or inaccurate depending on your device and network, and must not be relied on for safety or emergencies.
11. Changes to these terms
We will announce changes in the app and on this page 7 days before they take effect (30 days if they affect you adversely).
12. Governing law
These terms are governed by the laws of the Republic of Korea, without depriving you of protections given by the mandatory laws of your country of residence. Disputes will be resolved by the competent court under Korea’s Civil Procedure Act, unless your local law gives you the right to bring a claim in your home courts.