Nowadays ,     mobile/smartphone    processors (ARM-based ) are used ( or modified to fit ) in Laptops and  Tablets , but   mobile/smartphone    processors ( ARM-based )  are not comparable to PC processors ( INTEL-based )  in terms of performance .

If  Laptop/Tablet  manufacturers ,  switch to ARM based processors, their product will be very limited in the software it could run . A good example is the Snapdragon Laptops and the Snapdragon Tablets that are available today .