I did this over 5 yrs ago, it’s good for privacy but I found it annoying that you couldn’t have regular apps like normal phones. Maybes that’s changed now, I may look into getting another graphene OS phone
Discussion
I can use just about any app. I'm not sure I've had any issues with any because of graphene. Being a DeGoogled phone, I naturally don't use Google applications.
Honestly, like it so much, I may go with a tablet version as well as another phone.