The Internet is not very good in Nepal, but mobile coverage is increasing and is now in some of the popular trekking areas. Thamel in Kathmandu and Lakeside in Pokhara have the fastest connections, and all of the major towns have mobile internet. You can choose to use a foreign SIM card in Nepal, but it is much cheaper to simply buy a local SIM card. State-owned service provider Nepal Telecom (NTC) has the widest coverage area, and it offers pre-paid SIM cards with CDMA service. Privately owned Ncell is the country's largest mobile network provider. Regardless of the provider, getting a SIM card is as easy as walking into a corner store with a copy of your passport and signing up to get a card on the spot. If you want to make international calls, there are a number of shops that provide you with cheap ways to do so. You can access free WiFi in most guesthouses and hotels but most likely not while trekking. If you're staying in a remote area, it's a good idea to see if there is a generator in case the electricity goes out.