Terms of Service

Last updated: 25 September 2026

1. Who we are

ZeroPercent is a trading name of OppBox Ltd, a company registered in England & Wales under the company number 17351386 ("we", "us", "our"). You can reach us any time at [email protected].

These terms cover the ZeroPercent iOS app, the website at zeropercentapp.com, the web app at zeropercentapp.com/me, the rescue sign-in at zeropercentapp.com/rescue, the family invite pages, and the pages where someone agrees to be reached (zeropercentapp.com/c/). Together, these are "ZeroPercent" or "the service".

2. Agreeing to these terms

By creating an account or using ZeroPercent, you're agreeing to these terms. If you don't agree with them, please don't use the service. And if you've already signed up, you can delete your account in the app at any time.

These terms are between you and us. They are not between you and Apple. Apple distributes the app and handles payment, but Apple is not responsible for the service or for supporting it. Apple and its subsidiaries can enforce the parts of these terms that relate to your use of the app on an Apple device.

3. Who can use ZeroPercent

You can create a ZeroPercent account of your own if you're 16 or over, or such greater age as the law of your country requires for you to agree to these terms. Where that age is higher than 16 where you live, that higher age applies to you instead.

If you're 13, 14 or 15, you can use ZeroPercent only by being invited into a family. Someone else creates the family and sends you an invite code; you can't set one up on your own, and your membership doesn't go live until an adult (18 or over) who runs the family approves it.

You need to be 13 or over to use ZeroPercent at all. There is no version of the service for under-13s, and we don't knowingly let anyone under 13 create an account.

If you're under 18, someone who runs your family approved you joining and is responsible for how the family is run; if you're under 16, that person is an adult (18 or over). You still have your own account and your own rights over your data, and you can use them without asking anyone.

Two different ages apply inside a family, and they do different jobs:

• Admins are 16 or over. An admin runs the family: they invite people, approve who joins, change roles, remove people and set the family code word. Whoever creates a family is automatically one.
• An adult means 18 or over. If anyone under 16 is in a family, that family must always include at least one admin aged 18 or over. While that's the case we won't let the last such adult leave, be removed, be demoted, or delete their account, because doing so would leave a child with no adult responsible for them.

So two 16-year-olds can run a family between themselves, but a 13-year-old can only be in one that has an adult in it.

4. What ZeroPercent is, and is not

What it is. ZeroPercent does two things. It shows the adult(s) who run your plan that your phone still has charge and that your backup is set up. And if your phone dies, is lost, or is stolen, it lets you borrow any phone, open zeropercentapp.com in a browser, prove who you are, and reach the people you chose in advance: by text, or, on Pro plans, by a call.

5. Your account

Your mobile number is your account. We verify it with an SMS code, and we also ask for your name and date of birth. Your date of birth isn't decoration: it sets the age rules above, and it's one of the three things you'll be asked for if you ever sign in from a borrowed phone.

So please:

• Give us a mobile number that is genuinely yours, and a real date of birth. If either is wrong, the rescue sign-in won't work when you need it.
• Keep your rescue PIN to yourself. We store it only as a salted hash, so we can't read it back or recover it for you. But anyone who has your number, your date of birth and your PIN can start a rescue session as you.
• Tell us if you change your number, and tell us straight away if you think someone else has access to your account.

One account per person. Please don't share an account or set one up in someone else's name.

6. Families

A family is a small group (up to six people). The people who run it can see every member's battery level and readiness. A family has an owner and can have other admins; between them, they run it.

If you're an admin, you're telling us you're entitled to be one. By creating a family, or by accepting an invitation that makes you an admin, you confirm that: you're 16 or over; you have the agreement of the people you invite to share their battery level with the family; and if anyone in the family is under 16, an adult responsible for them is an admin too. You're responsible for how you use those powers: who you invite, who you approve, and who you remove.

Setting up a family is free, and so is being in one: the family screen, battery sharing, the low-battery alerts and texting for help from a borrowed phone cost nothing and don't expire, for up to six people. What a paid plan adds is voice calls and more than three backup contacts, and it has to cover everyone in the family for anyone to have them. Only the person who sets the plan up pays. Everyone they invite is covered at no cost to themselves, including under-18s. If the plan ends, voice calling stops and nothing else does: every member keeps their account, their family, their backup contacts and their rescue access.

• Admins invite people, approve under-18s joining, and can remove any member from the family at any time. If you're removed, you keep your ZeroPercent account, your backup contacts and your rescue access. You just stop sharing battery visibility with that family.
• What joining a family means. When you accept an invitation, the people who run that family can see your battery level and readiness, including people who come to run it later, because admins can invite and approve new members and change roles. If you'd rather not share with someone, you can leave at any time.
• Members can leave a family whenever they like.
• Reaching each other on a plan. Everyone on a plan can reach everyone else on it in a rescue. To join, you tick to agree to that (if you're 16 or 17 the wording is written for you). If you're under 16, the adult(s) who run your family agree for you when they approve you. You can switch off any individual in Settings and stay on the plan. Leaving the plan, or being removed, ends that agreement; if you rejoin, we ask again.
• Only the people who run a family see other members' battery. Everyone else sees their own.
• What the people who run a family see is narrow and fixed: a member's latest battery level with an honest timestamp, whether ZeroPercent is set up and ready, how many backup contacts they have, and when they last used the rescue sign-in (the time, never the messages). They also receive security notices about a member's account: a sign-in on a new device, a ZeroPercent PIN change, repeated failed rescue sign-ins, and a lockout. Never who a member's backup contacts are. Never location.
• Only invite people who want to be in your family. Don't use a family to keep tabs on someone who hasn't agreed to it.

7. Backup contacts

Backup contacts are the people you'd reach from a borrowed phone. You choose them, and they're visible only to you.

Backup contacts must be 16 or over. Someone under 16 can only be reached as a member of a family plan.

When you add someone as a backup contact, you're telling us they would expect to hear from you this way. Please tell them first. You send them a link from your own phone, and they agree on our website with a one-time code; until they do, a rescue can't reach them. People invited before 25 September 2026, or by an older version of the app, may instead have agreed by texting SAVED to our number, and that still counts. If someone asks to be taken off your list, remove them. They can also ask us directly, and we will remove them whatever you say.

8. Rescue sessions

A rescue session lets you use ZeroPercent from a phone that isn't yours. You answer three things you already know (your number, your date of birth and your PIN) and you get a short, time-limited session (about 15 minutes) showing your people, with only the last three digits of each number.

• Texting your people is free on every plan. Voice calling is a Pro feature.
• Your contact sees the message came via our relay, along with your name.
• We store nothing on the borrowed phone once the session ends, and you can end it yourself with one tap.
• Sign-in attempts are rate-limited. If you're locked out for a while after repeated failures, that's the protection working as intended.
• Please return the borrowed phone, and don't use someone's goodwill to do anything other than reach your people.

9. Fair and acceptable use

ZeroPercent exists so people can reach each other in a bad moment. Using it for anything else spoils it for everyone. So don't:

• Use the text or call relay to send marketing, bulk messages, scams, or anything else unsolicited.
• Harass, threaten, stalk, impersonate or abuse anyone, through the relay, through a family, or anywhere else in the service.
• Add people as backup contacts to contact them against their wishes.
• Set up an account or a family for someone who hasn't agreed to it, or pretend to be someone else.
• Try to break, overload, reverse-engineer or get around the security of the service, or automate access to it.
• Use ZeroPercent to break the law, or in a way that would put us in breach of ours.
• Give a false date of birth, or help someone get round the age rules.

If you see someone misusing ZeroPercent, tell us at [email protected].

10. Subscriptions and payment

ZeroPercent is free for your whole family, up to six people, and texting from a borrowed phone is always free on every plan. What you pay for is voice calls and unlimited backup contacts, not the people. A plan covers voice for a number of people, and it has to cover everyone in the family for anyone to be able to call.

On Pro and Pro Family, only the person who sets up the group pays. Everyone they invite is covered by that plan and is never charged for it. “Global Voice” means you can call from anywhere in the world; the people you call must have a number in a country ZeroPercent serves. Features and prices can differ by country; the App Store shows what applies where you are.

Some plans offer a one-month free trial to people who have not had one before; the App Store shows whether you are eligible before you subscribe. When a trial ends, the subscription starts and Apple charges you, unless you cancel at least 24 hours before the trial ends. After that, a subscription is charged monthly or yearly, whichever you chose, and you can cancel any time in your Apple Account settings. Yearly plans cost about a third less than twelve months of the monthly price.

Prices include VAT where it applies. If we change a price we'll tell you at least 30 days before it affects you, and you can cancel rather than accept it. Deleting your account does not cancel a subscription either; cancel it first in your Apple Account settings.

How billing works

• Subscriptions are bought and billed through your Apple Account. We never see or handle your payment details.
• They renew automatically each month until you cancel. Apple charges you within 24 hours before each renewal.
• You cancel in Settings → your name → Subscriptions on your iPhone, at least 24 hours before the next renewal. Cancelling stops the next payment; you keep Pro until the end of the period you've paid for. Deleting the app does not cancel a subscription.
• Refunds are handled by Apple under Apple's refund policy, not by us. If you think something has gone wrong, ask us anyway. We'd rather help you than leave you stuck.

Your 14-day cancellation right

Under the Consumer Contracts (Information, Cancellation and Additional Charges) Regulations 2013 you normally have 14 days to change your mind about a digital service bought online.

Pro starts working the moment you subscribe. By subscribing you're asking us to start the service immediately, and you acknowledge that once it has started you lose the right to cancel under those regulations for the period you've already begun. This doesn't affect your other rights. In particular, if the service isn't as described or isn't of satisfactory quality, your rights under the Consumer Rights Act 2015 still apply in full (see section 15).

11. Your content

The things you put into ZeroPercent (your name, your backup contacts, the words in a rescue message) stay yours. We don't want anything more than we need to run the service.

You give us a limited, non-exclusive licence to store and transmit that content strictly to operate ZeroPercent for you: to show your contacts back to you, to relay your message to the person you chose, to keep your family's battery view working. That's the whole scope. We don't use your content to train anything, to build advertising profiles, or to sell to anyone. Our copy of a rescue message is deleted within a day of the session. Twilio, which carries it, keeps its own copy for 30 days and uses message data to protect its network, as our Privacy Policy explains. The licence ends when the content does: your account data goes when you delete your account.

You're responsible for what you send. Please keep it legal, and keep it something you'd be comfortable with the recipient reading.

12. Privacy

How we handle personal data is explained in our Privacy Policy, and cookies in our Cookie Policy. They are there to inform you. They are not contract terms.

13. Suspension and ending your account

You can delete your account at any time in the app (Settings → Delete account). That removes your profile, your backup contacts, your battery history and your family records, as described in the Privacy Policy. Deleting your account does not cancel a subscription; cancel it first in your Apple Account settings, or you'll keep being charged.

An account nobody has used for 18 months is deleted, with everything in it, after two warnings in the app that name the date. Opening the app before that date keeps it. The Privacy Policy (section 7) says exactly what counts as using it and who this never applies to. Between 13 and 15, an account that has been outside any family for 30 days is deleted a week after a notice in the app, because the app cannot be used without one (Privacy Policy, sections 5 and 7).

We may suspend or close an account if someone is seriously or repeatedly breaking section 9, if we're required to by law, or if an account is being used to harm someone. Except where the law or someone's safety makes that impossible, we'll tell you why and give you a chance to put it right first. If we close your paid account without good reason, we'll refund the unused part of what you've paid.

If we suspend or close your account and you think we got it wrong, email us with "Appeal" in the subject and a different person will look at it. A closed account's subscription still has to be cancelled with Apple; closing the account does not do that.

We may also stop offering ZeroPercent altogether. If we ever do, we'll give you reasonable notice so you can arrange another backup, and refund any period you've paid for but won't receive.

14. What we promise, and what we can't

We'll provide ZeroPercent with reasonable care and skill, and we'll be straight with you about how it works.

What we can't promise is that the service will be available without interruption or entirely free of faults. It depends on things outside our control: Apple's operating system and what it allows an app to do in the background, mobile networks and SMS carriers, internet connections, and the borrowed phone in someone's hand. That's exactly why ZeroPercent is a backup, and why section 4 asks you never to treat it as your emergency plan.

15. Our liability to you

Nothing in these terms limits or excludes our liability for death or personal injury caused by our negligence, for fraud or fraudulent misrepresentation, or for anything else that the law does not allow us to limit or exclude. Any wording anywhere that appeared to do so would be void, and we'd rather simply not write it.

Your statutory rights stay intact. If you're a consumer, the Consumer Rights Act 2015 gives you rights about digital content and services (that they're of satisfactory quality, fit for purpose and as described) and nothing here takes those away or cuts them down. Citizens Advice can explain them if you'd like an independent view.

Beyond that: we're liable to you for loss that is a foreseeable result of us breaking these terms or failing to use reasonable care and skill. We're not liable for loss that isn't foreseeable: loss that neither of us could have expected when you started using ZeroPercent.

In particular, and because it matters here: ZeroPercent is a backup that depends on Apple, on mobile carriers and on the internet. We're not responsible for loss caused by a message that a carrier fails to deliver, by a battery reading iOS didn't give us in time, by a borrowed phone with no signal, or by anyone treating the service as a substitute for the emergency services.

We only supply ZeroPercent for personal use. If you use it for any business purpose, we have no liability to you for loss of profit, loss of business, business interruption or loss of business opportunity.

16. Changes to these terms

We'll update these terms occasionally, when the product changes or the law does. If a change materially affects you, we'll tell you in the app before it takes effect and update the date at the top of this page. If you don't want to accept a change, you can stop using ZeroPercent and delete your account; if you're on Pro, we'll refund the unused part of the period you've paid for.

17. Law, complaints and contact

These terms are governed by the law of England & Wales, and disputes can be brought in the courts of England & Wales. If you live in Scotland or Northern Ireland, you can also bring proceedings in your own courts. And if you live elsewhere, you keep the protections of the mandatory consumer law where you live.

If something's gone wrong, please email us first. We're a small company and a real person reads it: [email protected]. We'd much rather fix it than argue about it.

We may transfer these terms to a company that takes over ZeroPercent; we will tell you first. If a court finds part of these terms unenforceable, the rest still applies. These terms are written in English, and the English version is the one that counts.

OppBox Ltd (trading as ZeroPercent), company number 17351386, registered in England & Wales.

Previous versions of these terms