Do I need a separate emergency app if Android already has a medical ID?

Not necessarily. Android’s built-in medical ID and emergency calling cover the basics well, and you should fill them in either way. A dedicated app adds things the built-in features do not: attaching your details to an alert you send, offline first aid guidance, offline maps, and tools like a compass or signalling torch.

How much phone storage should I set aside for offline maps?

Less than people expect for a local area — a few tens of megabytes covers a town at usable zoom levels. Detailed coverage of a large region grows quickly. Download the specific areas you actually travel through rather than an entire country.

PreparednessPublished 21 August 20267 min read

Emergency preparedness: what should you actually keep on your phone?

Most advice about emergency preparedness on a phone amounts to a list of apps to install. That is the least useful part of it. Apps are easy to add later; the things that genuinely matter are the ones you cannot create in the moment — stored information, working offline copies, and a small number of settings that are awkward to change under pressure.

Here is what is worth the effort, roughly in order of how much difference it makes.

Information you cannot look up later

The single most valuable thing on your phone in an emergency is information about you that someone else might need and you might not be able to give them.

Blood type, if you know it
Allergies — especially drug allergies, which change what a paramedic can give you
Current medications and doses
Ongoing medical conditions: diabetes, epilepsy, heart conditions, anticoagulant use
Emergency contacts, with their relationship to you noted

Android has a built-in medical ID accessible from the lock screen, and it is worth filling in regardless of what else you install. The advantage of a dedicated app is that the same information can be attached to an alert you send, rather than only being readable by someone holding your phone.

How the medical information card works in Offline Emergency ToolkitMedical information

A phone number you know by heart

This is the one item on the list that is not stored on the phone at all. If your phone is lost, dead or locked, every contact in it is gone. One memorised number — a partner, a parent, a close friend — covers the situation where you can borrow someone else’s phone.

It is also the single most useful thing to teach a child. A ten-year-old who knows a parent’s number by memory is better prepared than one carrying a phone they may not have with them.

Offline copies of anything you would otherwise search for

Anything you would reach for a search engine to find is worth having stored locally instead. Search requires a connection, and the situations where you need first aid guidance overlap heavily with the situations where connections fail.

First aid guidance stored in an app rather than bookmarked
A downloaded map of the area you live in and anywhere you regularly travel
Emergency numbers for any country you visit — they are not all 911
Your insurance policy number and your embassy’s contact details, as a note

Downloading map coverage is the one that people consistently skip and then regret. It takes a couple of minutes on Wi-Fi and it is useless to start after you have lost signal.

Downloading map areas for offline useOffline maps

Settings that are awkward to change under pressure

Lock screen access

Decide in advance what should be reachable without unlocking. Android lets you expose emergency information and emergency calling from the lock screen. Some apps can put an SOS action there too. The trade-off is genuine — anything reachable without your PIN is reachable by anyone holding the phone — so make the decision deliberately rather than by default.

Battery

Know how to turn on battery saver quickly, and know roughly what your phone does at 5%. A phone that dies is not a toolkit. If you rely on your phone outdoors, a small power bank is a better investment than any app on this list.

Emergency SOS

Most Android phones have a built-in emergency SOS triggered by pressing the power button several times. Find out whether yours does, what it is configured to do, and whether that is what you want. Many people discover it by accident at an unhelpful moment.

What is not worth bothering with

A few common recommendations that do not survive contact with an actual emergency:

A folder of ten single-purpose apps. You will not remember which one does what. Fewer, broader tools win.
Anything requiring a login to reach your own stored data. If it needs a password and a connection, it is not emergency information.
Screenshots of documents buried in a camera roll with 8,000 other photos. Store them somewhere retrievable.
Apps that require a subscription to unlock safety features. Whatever you rely on should still work when a card expires.

A ten-minute version

If you do nothing else, do this. It genuinely takes about ten minutes:

Fill in your medical ID with allergies and medications
Save two emergency contacts, and memorise one of their numbers
Download offline map coverage for your home area
Install one app that keeps first aid guidance available offline
Check what your phone’s built-in emergency SOS does

None of this is dramatic, and that is rather the point. Preparedness is mostly a set of small, boring decisions made early enough that they are already done when they matter.