Pete's dad (Albert Brooks) mentions his mom wanted to get an abortion - because "it was the 70's". Pete becoming 40 would indicate he would have been born in 1972. Roe V. Wade was not passed until January 1973.
When Debbie is having lunch with her dad, Oliver, he pulls out his iPhone and it's clearly showing the dock connector on the top, and the phone would be upside down. After Debbie picks the phone up, it is the correct way when she is flipping through pictures.
At Paul Rudd's birthday party, Albert Brooks tells Leslie Mann that he understands what is bothering her--she hates Jews. He then adds that this is odd, because her children are Jewish. Many Jews believe that the children of a mixed marriage are only Jewish if their mother is Jewish, or the mother has converted.
Oliver uses his iPhone upside down. When he shows Debbie a picture on it, the speakers are visible from the top. When Oliver excuses himself and Debbie picks up phone, the headphone jack and power button are visible from the top instead.