Cellphone and use of Visa credit card

Hello! How do I operate in order to make my cellphone active in Mongolia? If there is the prepaid-possibility, would that work in distant wilderness areas like Terelj and Khentii? Or is the direct satellite connection the only option out there? How about the chances for recharching the battery in the middle of nowhere? A functionable cellphone would be crucial in a possible case of emergency.
Are Visa card for shopping and Visa Electron for automatic use common/functionable in UB?

Foreign phone
It is not recommended to use your foreign phone, it is possible, but the cost is very high, even for local calls. Satellite phones will also work all over Mongolia but they are very expensive.

Recommendation
Bring with you, or buy in Mongolia a cheap cellphone that is open to accept any SIM card, they are available in several stores along peace road in UB. Than buy a local prepaid SIM card for about $3-$5 it comes with a large sum of minutes talk, and valid for a few months.

Cellphone companies in Mongolia
Mobicom - best coverage, GSM
Unitel - good coverage, cheaper, GSM
Skytel, CDMA
G-Mobile, CDMA

Coverage
All regions have coverage, and most populated areas including Terelj.
In the middle of nowhere, try to climb to a high point, you might get a signal.
A map of coverage by Unitel

Recharging battery
You can recharge in all populated vilages and towns.
Some fancy tourist Ger camps have electricity even in the middle of nowhere
Some Nomadic Gers have a wind or sun power panels to charge cellphone batteries, they also use cellphones (instead of smoke signals).
Some have a motorbike (instead of a horse) parked outside the Ger, to ride up the mountain to pick up a cellphone signal.

Visa is accepted in Mongolia.
There are many ATM's in Ulaanbaatar.
Check with your bank that you have a card for International use.
Some cads are issued for local use in your home country.
Visa Electron, should be accepted like any other Visa card.

Recommendation
Don't rely on your card for payments in Mongolia.
Use your card at the banks to get local cash.
You can get cash money with your Visa at all banks in UB.
Some banks are open 24h (Golomt bank).

Have a nice trip

Dan