How much data do you really need?

For regular navigation, allow roughly 5–20 MB per hour after the route and map area have loaded. Searches, satellite view, Street View, photos and live traffic can use more data. Downloading an offline map over wifi before you leave helps reduce your usage.

A WhatsApp video call can use roughly 0.3–1 GB per hour. The actual amount depends on the connection and video quality. Audio-only calls use much less data, and turning off your camera also reduces usage.

Actual usage can be higher than planned because of route changes, slow wifi, automatic uploads, background activity and changes in video quality. The 20% buffer gives you some room for those differences without immediately needing a larger plan.

You can use reliable wifi for large downloads, backups and streaming. However, wifi may not be available while you are travelling between places. Keep enough mobile data for maps, tickets, transport, messages and bookings when you are away from your accommodation.