Can I use my cell phone, smart phone, or tablet in Cuba?

Smart and Mobile Phones
Some U.S. carriers, such as Sprint and Verizon, now offer international roaming services for customers in the United States traveling to Cuba. If your carrier offers a roaming plan and your mobile phone is capable of roaming in Cuba, you should ask your carrier about any additional charges for voice calls, data, roaming and outgoing text messages that you may incur during your trip. We advise that you contact your current carrier for the most up to date information on usage before leaving 
Phone Rental in Cuba
Before you leave for Cuba, you can rent a compatible mobile phone from companies such as Cellular Abroad (offered by National Geographic), Cello Mobile, or Mobal for use in Cuba.  In addition to daily rental fees, you should expect to pay approximately $3 USD per minute of call time and up to $1.50 USD per outgoing text message. Depending on the type of phone rented, data may also be available at an additional cost. 
Other Carriers
Although your mobile phone or device may not have international mobile service or signal in Cuba, many guests, including our staff, bring phones, tablets, and other devices to access their address or contact lists, and for email and text usage when connected to hotel WiFi. Other smart-phone functions, including camera, alarm clocks, music storage, flashlight and apps not requiring internet, will work.
You may purchase WiFi access by the hour or day at certain hotels. This will allow your smart phone—but not mobile phones—to access email and instant messaging applications. 
In summary, most guests appreciate that their trip to Cuba virtually requires them to unplug.