Annoying circle with 3dot, plS help me to fix

I just bough Samsung galaxy s6 , i come from galaxy S4 , and many apps or game that i have installed in S4 now got circle dot floating icon appear in righ side ......its really annoying i cant remove it, is there any custom firmware that fix it? why my lg g3 samsung s4 or nexus 5 dont have this issue??

is related with lollipop? and app service? or just samsung s6?

HELPP

its like this circle:

IMAGE

seriously why i need 10 post to post a pictture..... pff....