How much data do I need for a trip? App by app

The question everyone asks before buying a data plan is the same one: is 3 GB enough? Is 5? Should I just get unlimited? The honest answer is that it depends on what you do with your phone. What you can do is measure it: here is what each app really uses, three traveller profiles with a number attached, and the tricks that halve your consumption without you noticing.

What each thing costs you (rough figures)

These are averages, and apps change their compression every few months, but the order of magnitude has held for years:

Activity	Approximate use
WhatsApp, messages and small photos	Almost nothing: a few MB a day
WhatsApp voice call	~30 MB per hour
Video call (WhatsApp, FaceTime)	~300 MB per hour
Google Maps navigating a city	5-10 MB per hour (with the map downloaded, near zero)
Browsing and reading news	50-100 MB per hour
Instagram or TikTok (just scrolling)	150-500 MB per hour, depending on how much video appears
Posting a story or a reel	20-50 MB each
Spotify (standard quality)	40-70 MB per hour
YouTube or Netflix at standard quality	500 MB - 1 GB per hour
Video in HD (1080p)	1.5-3 GB per hour
Photo backup to the cloud	Whatever the photos weigh: 100 photos ≈ 300-500 MB

Notice where the money goes: video. Maps, messages and translation barely register. What empties a plan in two days is watching series on mobile data, letting photos upload themselves to the cloud, and infinite reel-scrolling on the metro.

Three profiles, three numbers

The light traveller (1-2 GB a week)

Maps so you do not get lost, WhatsApp with family, looking up a restaurant, checking email, the odd photo to the group chat. Social media only on wifi.

Around 200-300 MB a day. A 3 GB plan covers a week comfortably; for two weeks, 5 GB works.

The normal traveller (3-5 GB a week)

All of the above, plus a while on Instagram or TikTok each day, a story posted from the beach, a short video call and music in your ears while you walk.

Around 500 MB - 1 GB a day. For a week, 5 GB is the comfortable number. For ten days or more, 10 GB or an unlimited plan.

The creator or digital nomad (over 1 GB a day)

You upload video, take long video calls, work off your phone or tether a laptop, and watch things on the train.

2-3 GB a day, sometimes more. A per-GB plan runs dry in three days here; what fits is unlimited by the day or a big plan (20 GB and up).

If you are torn between two sizes, take the bigger one: the price gap is usually small, and running out on your last day — with a flight to check in for and a hotel to confirm — is the worst possible moment.

A real week, with the sums

A concrete example so the table lands. Seven days in Lisbon or Bangkok, normal use:

• Maps: an hour a day with the map downloaded → about 20 MB for the week.
• WhatsApp with text, voice notes and photos → about 150 MB.
• Instagram half an hour a day, with video → about 1.5 GB.
• Three stories posted each day → about 600 MB.
• A ten-minute video call every other day → about 150 MB.
• Looking up restaurants, timetables, tickets → about 300 MB.
• Spotify an hour a day out walking → about 400 MB.

Total: around 3 GB, and that is without downloading anything on the accommodation wifi. With photos auto-uploading to the cloud, the same trip becomes 5 or 6 GB. With two episodes of something on mobile data, 8. Which is why the short answer to “how much data for a week?” is 5 GB if you are careful, unlimited if you would rather not have to be.

Per-GB or unlimited: how to choose

• Per-GB wins if you know your habits, you are away for a few days, or the destination has good wifi where you sleep. It is usually cheaper for light use.
• Unlimited by the day wins if you do not want to watch a counter, you are going to post video, you work off your phone or you tether. The more days, the cheaper each day works out.
• If you are visiting several countries, a regional per-GB plan saves buying an eSIM at every border.

What “unlimited” really means

Almost no travel plan is unlimited at full speed all day. The usual arrangement is a daily allowance (1 GB, 2 GB) at full speed and, once you pass it, reduced speed until the day rolls over. At that reduced speed (a few hundred kilobits per second) WhatsApp, maps and email are fine, and video is not.

That is a fair deal as long as you know about it: you never lose your connection, you never pay extra, and if you have a heavy day you get your full-speed allowance back. What is not fair is selling it to you without saying so. MovaSim’s plan pages spell it out with numbers; with other providers, look for the “fair use” small print.

Tricks that halve your use

1. Download the maps before you go. Google Maps → your profile → Offline maps → pick the area. Apple Maps has done it since iOS 17. Navigating on a downloaded map costs a fraction.
2. Download the language pack in your translator. Google Translate lets you take a language offline for both text and camera.
3. Low data mode. iPhone: Settings → Mobile Data → your eSIM → Low Data Mode. Android: Data Saver. It reins in background downloads and automatic video quality.
4. Cloud photo backup on wifi only. This is the biggest invisible cost. Set it in iCloud, Google Photos or Dropbox.
5. Turn off video autoplay in Instagram, X and Facebook, or at least set it to wifi only.
6. Download series and playlists on your accommodation’s wifi.
7. App updates on wifi only. One large app update can be half a gigabyte.
8. Tether with care. A laptop does things on its own — syncing, updating. If you connect it to your phone, mark the connection as metered.
9. Watch the counter. iPhone: Settings → Mobile Data shows use per app. Android: Settings → Network → Data usage. Reset it at the start of the trip and within two days you will know your real rate.

Gigabytes do not fix missing coverage

One thing that gets forgotten in these sums: gigabytes are what you can spend, not where you can spend it. An eSIM connects to a local operator’s network, and where there is no mast, no eSIM will help, however much data you carry. On mountain routes, small islands, national parks or boat crossings you will lose signal just as fast with 50 GB as with 1. The answer is not buying more data, it is downloading the area’s map before you set off and telling someone where you are going.

And if I run out

On a per-GB plan you can normally buy another and activate it straight away, with nothing to wait for. On an unlimited daily plan you never run out: the speed drops until the next day. Either way, keep the order email to hand — that is where you top up and check your usage.

For a specific country, the coverage and the apps people actually use change the sums: each destination guide has the adjusted recommendation. And if you are still not sure how an eSIM works, start with What is an eSIM and how does it work?.