I have two friends traveling to Paris next month and after giving them both tips on places to stay and eat (of course), I also offered them some tips to save money on credit card usage, cell phones/data usage overseas, and cautionary advice to keep their possessions safe. I'm passing on the information here because I think anyone who reads this blog probably loves to travel (as well as eat) so keep these links and info handy for your next trip:)
Before you leave, you may want to get a chip & PIN credit card (I got one from Bank of America) because many places like train stations and gas stations will not accept a US credit card for payment without a chip. If you are carrying enough cash to cover most transactions and want to only use a credit card for bigger purchases, then get a credit card which doesn't charge foreign transaction fees before you leave. The fees could amount to 3% OVER the purchase price! Make sure your cards (and passport) are always carried in an RFID safe wallet or simply wrap some foil around them.
Before you can use any of the SIM card options, you must have an unlocked phone,
so either go to your cell provider and have them unlock it or buy/borrow
an unlocked phone for travel. For cell phones and data, there are two providers of international phones/SIM cards/data plans which I would recommend if traveling to France (or several other countries). Le French Mobile was created in UK for students studying in France so their rates are substantially lower (starting at 20 Euros) than regular retail and their entire website is in English (recommended for longer stays). For most tourists from the US, Telestial has higher rates (about $50 USD) but easy options. If you are able or willing to translate the website info, the local French provider SFR has options for calls, texts, and data on prepaid plans and Simyo has deeply discounted rates (although I can't vouch for their service).
Since many people are taking their phones and tablets/laptops with them, it's helpful to have some applications installed in case they get stolen. I recently received a Nexus 7 for Christmas from the generous @John8600 and installed AVG which protects against viruses and theft for free on Android devices. If you have an iPad or iPhone, and plan on taking it with you on a trip, you might want to install an application like gadgettrak.com for $19.95 a year (for phones) or lojackforlaptops.com $19.99 year (for laptops). It gave me peace of mind to know I could remotely lock, erase, track my device, and give the location of my stolen device to local law enforcement!
No matter where you travel, keep copies of your passport, tickets and credit cards somewhere (I have scanned mine and emailed them to myself) because it is always better to be prepared for the worst while expecting the best :)