Why travelers love it: Around the world, hotels, tour guides, drivers and restaurants now use WhatsApp to confirm bookings and send directions. Once you're set up, you can also stay in touch with family back home without paying international calling or text rates.

Cost: The app is free. Messages and calls use your Wi-Fi or mobile data, so the cost depends on your connection (more on that below).

Step 1: Get set up (about 10 minutes): Do this at home on Wi-Fi, before you leave.

1. Open the App Store (iPhone) or Play Store (Android). Search for WhatsApp Messenger and tap Install or Get.

2. Open it and agree to the terms.

3. Enter your phone number.

4. Enter your code. WhatsApp sends a 6-digit code by text message (or by phone call if you ask). Type it into the app. This proves the number is yours.

5. Add your name and photo.  A first name is fine. A photo is optional, but it helps friends recognize you.

6. Allow contacts. When asked, tap “Allow” so the app can show which of your contacts already use WhatsApp. They'll appear in your list automatically.

⚠️ Important: that 6-digit code is for you only. Never give it to anyone, even if they seem to be a friend or family member. More on this in the safety section.

Step 2: Send your first message

1. Tap the “new chat” button (a green circle or speech-bubble icon).

2. Pick a contact.

3. Type your message at the bottom and tap the arrow to send.

Check marks show what happened:

- One gray check: sent

- Two gray checks: delivered

- Two blue checks: read

Note: Contacts who don't have WhatsApp won't appear. You can send them an invite by text, or just keep texting them the usual way.

Step 3: Send photos and voice messages

- Photo: tap the plus or paperclip icon next to the message box, choose “Camera” or “Photos”, pick your image and tap send.

- Voice message: press and hold the “microphone” icon, speak, and release to send. This is great when typing is a hassle.

Step 4: Make a voice or video call

1. Open a chat with someone.

2. Tap the “phone” icon for a voice call or the “video camera” for a video call.

3. When they answer, you can talk, and on video you'll see each other.

Over Wi-Fi, these calls are the easiest way to keep in touch from the road. Video calls use a lot more data than texting or voice calls, so use Wi-Fi when you can.

Step 5: Share where you are: This pairs well with last issue's what3words.

1. In a chat, tap the “plus or paperclip” icon.

2. Tap “Location”.

3. Choose “Send your current location” (or share it live for a set time if you're meeting someone).

Your travel partner, driver or host sees you on a map.

Step 6: Group chats for trips: Traveling with friends or family? Create a group so everyone sees the same plans.

1. Tap “new chat”, then “New group”.

2. Pick the people, tap the arrow, and name the group, like "Fall Foliage Trip."

3. Everyone can share photos, times and meeting spots in one place.

Step 7: Avoid surprise charges when traveling: This is the step many travelers miss.

- On Wi-Fi, WhatsApp costs nothing extra. Hotel, café and airport Wi-Fi are fine.

- On mobile data abroad, your phone company may charge roaming fees unless you have an international plan. WhatsApp itself isn't charging you, but your phone company might.

- To stay safe: Before you travel, check your carrier's international plan options. If you don't have a plan, turn off “mobile data” (or “data roaming”) in your phone's settings and use Wi-Fi only.

- Tip: Try WhatsApp on Wi-Fi before the trip, so you know it works.

Step 8: Stay safe: WhatsApp is very popular, so scammers target it. A few rules cover most cases:

1. Never share your 6-digit code. If you get a code you didn't ask for, ignore it. If someone asks you to send it, it's a scam.

2. Be suspicious of messages from "friends" asking for money or codes. If a friend's account has been taken over, the scammer will message people in their contacts. Call the person to check, using their regular phone number.

3. Don't click unexpected links or open files from unknown numbers.

4. Turn on two-step verification. This adds a PIN of your own. In the app, go to “Settings”, then “Account”, then “Two-step verification” and follow the prompts. Write the PIN down somewhere safe.

5. Your messages are private. WhatsApp encrypts messages and calls, so only you and the person you're talking to can read them. That doesn't protect you from tricks, so the rules above still apply.

Try it this week: Download the app, send a message to a friend or family member, and try a quick video call over Wi-Fi. Five minutes of practice at home beats figuring it out in a foreign airport.