Bitcoin is a modern digital form of currency, the reality of which has not yet been fully elucidated. Furthermore there is rapid change in its rate resulting in its instability and in many countries it lacks government backing. Considering this and several other similar reasons, scholars are doing research on these and various other aspects of this currency, but so far the application of Shariah principles to it and its Shariah status has not been fully clarified, so at present transactions through it should be avoided.
Allah knows best
Darulifta Al Ikhlas,Karachi