What should I set up now in case my phone dies, gets lost or has no signal?

Three pages in this library are about the day the phone cannot help. Write down the numbers your phone remembers for you is the battery that dies, the phone that is locked, lost, stolen or smashed, and the number you need from it. Download the map while you still have signal is the screen that shows a dot on a blank background. Back up what you can’t replace, then prove it opens is the photos, papers and projects you could not replace. Each is work done once, on an ordinary day.

Learn one or two numbers by heart, carry them written down, and fill in your phone’s emergency information. Write down the numbers your phone remembers for you says that because in an emergency the phone may be dead, locked, broken or gone, and your ordinary contacts sit behind the passcode. Your own memory can go too: people who had been hurt or in shock describe forgetting numbers they knew perfectly well, and one says a written number is what got them help when their phone was destroyed. So the page puts the number in three places, which work together rather than instead of each other.

In your head: many people say learn at least one or two numbers by heart, a parent, a partner, a close friend, so you can dial them on any phone. Choose someone who picks up unknown numbers, because one person warns a memorised number is useless if the person never answers a call they do not recognise, and one person’s answer is a parent or older relative with older phone habits. Tell them now that a call from a number they do not know might be you. On paper: many people say carry a written list in your wallet or bag, and the US federal preparedness site’s family plan says the same, a copy for everyone in a wallet, bag or backpack, and a copy on the fridge. On the phone, where a stranger can reach it: many people say fill in your phone’s emergency or medical information, which can be shown from the lock screen without the passcode. Put in the medical conditions you live with, the medicines you take, your allergies, and one or two emergency contacts; one person warns it stays empty until you fill it in, and some people note the menus differ between phone makers, so search your settings for it. Keep the contacts current; one person reminds readers to change them after a break-up.

Whether emergency staff actually look at your phone, people who do the job disagree. Some say crews routinely check the lock-screen information to identify someone and reach their family; others say responders rarely, if ever, look at a phone while treating someone, and that a bracelet or a card in the wallet is faster and more reliable. The page’s own reading is that the phone’s page helps most later, once you are stable in hospital, and a visible medical alert or a wallet card at the scene. If you live with something a crew must know in the first minutes, diabetes or a severe allergy, that is the case for something they can see without touching your phone.

Some people add the non-emergency number for your local police, fire and ambulance services, so problems that are not emergencies do not go to 911 in the United States or 999 in the UK, and one person adds an emergency vet and a poison line for pets. For people, the page gives US Poison Help, 1-800-222-1222, and in the UK, NHS 111 for urgent advice that is not an emergency. The federal family plan also suggests someone out of town as a contact, because in a disaster a long-distance call can get through when local lines are jammed, and it says a text may get through when a call will not.

Download the map of the whole area before you lose signal. Download the map while you still have signal says many people explain the half-truth that catches people: the position comes from satellites and works anywhere the sky is open, in airplane mode and with the SIM off, but the map itself is fetched over the internet as you move, and with no data and nothing saved the screen is a dot on a blank. So on home wifi the night before, the page says, find the setting for offline or downloaded maps, select the whole area you are going to, the city and the roads in and out, or the park and the route to it, and save the places you will need. Then charge the phone and, if you have one, the power bank. Downloaded maps can expire or be deleted after a period, some people say, so download close to the trip and check the date before you leave.

That page puts three things before the technical part. If you are going anywhere remote, tell one person you trust the route and the time you expect to be back, some people say, one trusted person and not a public message, because some people say broadcasting where you will be alone is its own risk. Airplane mode saves battery in a dead zone, some people say, by stopping the phone hunting for a signal, and some people say it also stops every call and text reaching you. Where there is no signal there is nothing to lose; where there is a weak or patchy one, turn off mobile data instead and stay reachable. And the numbers: across the European Union 112 reaches the emergency services free from any phone, and national numbers still work beside it; it is 999 in the United Kingdom, 911 in the United States and 000 in Australia. In the United States the page says a 911 call is worth trying even with no bars from your own network, and it flags the carrier rule behind that for review; with no tower in reach at all, no phone can call, which is the case for the trusted person and the paper map. Many people say a paper map is worth carrying as a backup, because it needs no charge and works when the electronics fail, and what decides it, they say, is the length of the trip, the terrain, and how good you are with paper.

Keep at least three copies of anything you cannot replace, on at least two different kinds of storage, with one copy outside your home, and open a file from the backup now and then to prove it works. Back up what you can’t replace, then prove it opens starts small: pick the one folder you could not replace, family photos, scanned papers, the work you are proud of, and copy the whole folder to one other place, an external drive, a USB stick or your cloud storage. Unplug the drive when it finishes, then open two or three files from the copy, not the original. Then build to the rule many people give, called 3-2-1, which the US government’s own backup guidance states the same way: keep three copies of any important file, the original and two backups, on two different types of storage, so that one kind of failure cannot take both, and keep one copy away from your home. Some people say a backup in the same house is not enough, because a fire, a flood or a burglary takes the computer and the drive beside it together.

Some copies are not really separate, the page warns. A second partition on the same drive dies with the drive. Some people warn an external drive that is always plugged in is exposed to the same viruses and ransomware as the computer, and the UK’s National Cyber Security Centre says the same: ransomware can move to attached drives automatically, so disconnect the drive when the backup is done. A syncing folder is not a backup either, some people say: if you delete a file on your computer, it can disappear from the cloud too, though some of those services keep older versions of your files for a while. And cloud storage only lasts as long as your account and subscription do, some people say, and services can close; the page says limits like these are the reason the cloud should be one copy rather than the only one.

Of the things the page says are easy to forget, two are on the phone. One person says that losing the phone can lock you out of your accounts through the codes in your two-factor authenticator app, even if your photos are safe. And one person says a phone’s memory card is not protected by the phone’s lock, so encrypt it if you use one; if you encrypt a backup and lose the password, the page warns, the files are gone for good. Once the first copy exists, make it automatic if you can, with your computer’s own built-in backup tool or your phone’s cloud backup, and now and then restore a few files to a new folder to check they are whole. It is safe to test: you are copying the backup, not touching the original.

Who this is not for. If there is nobody you would put on the card, the numbers page says people did not solve that and it will not pretend to; a wallet card with your medical needs, and a visible alert if you have a condition that matters, still help the people treating you. If you are going beyond where a phone can be trusted at all, days on foot, real cold, no towers, the map page says it is not enough: many people say carry paper, one says a compass with it, and the skill to use them is a different page’s job. And the backup page is for a household’s own photos, papers and projects, not for running a business’s or a school’s systems. The numbers page and the map page give no phone-specific steps: the first says they differ by make and model, the second that such steps would be stale within a year.