Jun 18, 2018 - 12:23 PM
in reply to arajnish
Personally I would focus on the data and make calls via Skype, Whatsapp, etc. You can do that with a SIM card or a Wifi hotspot (and keep your own SIM card in place). If you prefer actual phone calls (not online), then the first card that you mentioned is a good option. It offers data and calls in those 3 countries (and more). You'll find details here: www.myswissalps.com/si mcard.
I don't think I've heard of the second option you mentioned. It sounds like a card for the United Kingdom, which is not where you are going.
Different options will be available at the airports, but I don't have details about that.