Hubby is having a hard time with the kids

After he comes home from work he gets so angry when the kids are just constantly crying and fighting (4 year old girl 2 year old boy) and the weekends are just as bad he gets so angry and has to walk out of the room and go play on his phone I do admit they cry and fight a lot but it’s nothing compared to other kids I have seen. I try and tell him this is what having kids is like and he understands but still is so quick to get frustrated. Is there any other advice I could give him that will help him to not get so frustrated so easily? Thanks