The main difference is the charger we can see. The fk8 is the magnetic charger and the fk88 pro is the wireless charger and the box. Both box is also different. The fk88 is white cover and the fk88 pro is black color and the third difference is the manual style. The fk88 has two menu style and the fk8 pro has 3 menu style and we can have a check and then the cellular style. So these two menu styles are the same and then the fk88 pro has one more list style. While the fk88 does not have this style and we can check the outward appearance. The fk88 has a charging interface at the back, but the fk88 pro does not have a charging interface. Then let’s compare the watch faces. So all the watch faces are the same and both watch can customize watch faces through the app Music Music. Then let’s compare the functions: Music, Music, do Music Music. So all those functions are the same. Then we can check the charging charging. The fk88 has a charging symbol in the screen, but there is no symbol in the fk8 pro and only the charger will have a green light. So above is all details today.