Caution — Roaming!
Roaming is a communication service of your mobile operator provided in another country. It is, of course, very convenient that you can call your permanent number, even when you are abroad. You can call and you. But roaming services are very expensive, and often incoming calls are more expensive than outgoing calls. As a rule, Internet roaming is even more expensive and can reach up to 15 dollars 1 per megabyte. It should be noted that some mobile operators hold special promotions to reduce prices and roaming tariffs — but this service must be activated separately. The general rule is this: when going abroad, check with your carrier for roaming rates in the country of destination, as well as about promotions and discounts.
Despite all this, we would recommend using the roaming service carefully, and if you are not sure, it is better to turn off at least mobile internet when roaming, because the phone can download updates without your knowledge.
In the settings of smartphones and tablets there is such an item — do not use the Internet when roaming. Better yet, turn off mobile data transfer.