The same way you do with any other phone number.
If the US mobile phone is in international roaming mode, you may be able to dial its normal US number. If the phone has swapped in a UK SIM card, you will need to dial the UK number.
No - usually the mobile networks will do all the 'hard work' for you.
you have to have long distant calls and also know a phone number that leads there
In the UK they call it the W995i in US they say W995a
yes if you get international calling or buy a calling card.
Assuming it's a contact in the phone's memory - just do exactly as you would if both phones were home in he UK. The network will sort out the logistics and connect both phones.
The mobile phone number remains the same no matter where you take your phone - callers do not have to guess where your phone is before they dial you. In this case, the US caller would call you in the same was as calling any other UK telephone number: international access code 011, then country code 44 for the UK, followed by the full mobile number ignoring the leading zero. For example, 07345 345678 would be dialled as 011 44 7345 345678 from the USA.
Just like you would to any other place - by using the right telephone number. For instance if you're texting from the UK to a US phone, you need to use the US country code, and to drop the first zero in the cell phone prefix. If you're texting to a UK phone in the US, simply use the same number as if the phone was in the UK. The network jeeps track of where the phone is. Note that some contracts and prepaid phones might not allow international traffic.
I think that the phone number is still the same so you would call it as if it is in the US. To answer my own question, (they have been here and now gone home again), you dial +1 followed by cell phone no.
UK.
NO!
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