Mobile communications and the Internet in the Crimea for tourists
Mobile communications in the Crimea is billed as domestic roaming (not international), so no need to buy SIM card from local operators on arrival. In addition, while in the Crimea are sold SIM cards the only Russian operator MTS. To save, it is best to have your cellular provider to enable options to reduce the cost of roaming in Russia like "Everywhere as houses" from MTS.
Unfortunately, the special options are not all operators operate on the territory of Crimea. At the time of writing (April 2016) on the territory of Crimea and Sevastopol is effective only special option "Everywhere as houses" from MTS, and other operators to offer roaming only. This means that incoming calls are also charged, and outgoing calls will not be cheap. So today is the best operator to travel with your home SIM card in the Crimean MTS.
The situation is constantly changing, and possibly other operators will also include the Crimea and Simferopol in your area, special options, and yet carefully read the description of the special options and rates.
Mobile Internet 2G and 3G is present almost everywhere, but works very poorly, and in some cities not at all. For example, in June 2015 for a 5 day stay in Yalta, the authors did not manage even once to access the mobile Internet, while in the suburbs of Yalta (big Yalta) it somehow worked. 4G has only started to develop in early 2015 with local operator K-Telecom. Don't forget that the difficult terrain here makes it difficult to work cell, and not everywhere there is a signal of good quality.
As for the cost and tariffs, with the mobile Internet all the while a voice which is similar to the hundredth. So far, the most profitable operator – MTS with their options of the Internet throughout Russia, and they include the territory of Crimea and Simferopol. Other operators are billed Internet traffic in roaming, and is very easy to "fly" into debt, it is the megabyte (and it viewing one or two pages) costs 2 rubles.
As for Wi-fi Internet, it is available for free in almost all hotels and guesthouses. To check availability in a particular hotel in the hotels before booking.