HOW TO CHANGE CHARACTERISTIC NAME AND SERVICE NAME FROM CODE

HI friends 

i am vary new to bluetooth ,

1.the problem is i want to give custom name for the UUID characteristics, as of now in mobile app it displaying unknown service ,and unknown characteristics .

2.i found some solution like in nrf connect mobile app if we long press on characteristics  we can edit the name but it is only possible locally  if we use other mobile again it will show same unkown characteristics .

3.please give any solution to change the service name and characteristics name globally llike if you scan and connect  with different mobile it should not change .

thanks in advance