Whenever you venture outside your carrier's network, you risk data roaming fees. ... Roaming allows you to make calls, send texts, and use wireless data even when you're outside of your network's boundaries. The downside, of course, is that roaming data usually comes with extra charges to your account.

Do I want data roaming on or off?

Roaming charges can get expensive, so if you're traveling outside your cellular plan's coverage area (which generally means international travel), you might want to turn off data roaming on your Android device. Don't worry about being left without internet.

Is data free on roaming?

Also, there will be no additional data charges on national roaming. Home data packs for customers will apply even while they roam across India.