One tip that frequent travelers dole out to non-frequent travelers is this: buy a local SIM the moment you land, because international roaming rates will be the death of your wallet. Local SIMs are usually sold for cheap and even though you might not consume all the credits from your initial top up, at least you won’t be slapped with atrocious roaming rates by your regular network.
There used to be no alternative to this–but that was before KnowRoaming came along. KnowRoaming is a sticker that you’re supposed to stick onto your SIM card using the included applicator. Once affixed, you’ll be able to connect with local networks wherever you are in the world by firing up the KnowRoaming app.