All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
There is nothing wrong with selling mobile phones and even cameras themselves whether in that country or another as long as one does not know nor does he think mostly that the buyer of the set intends to use it in prohibited matters. So, if that is known from his condition, then selling that set for him is prohibited, even if it does not have a camera or the like.
In any case, having a camera in a mobile phone or any other set does not affect the ruling of dealing with Muslims and non-Muslims who are in that country or any other country.
We have pointed out in Fatwa 91934 the permissibility of taking pictures with cameras as long as the scene does not contain a religious prohibition.
Also, we have pointed out in Fatwa 86451 that selling the means that may be used in lawful or unlawful matters is permissible as long as the seller does not know that the buyer will use them in prohibited matters.
Allaah Knows best.