It is one less form to fill out and oh, how I hate paperwork. U.S. Customs and Border Protection now has a Mobile Passport Control App.
Download it for free from Apple and create a profile with your passport information. Each time you arrive back in the U.S., complete the new trip section. You’ll get a QR code on your smartphone or tablet that you show to the customs officer. The best part is you get to skip those long customs lines.
To really make customs a breeze, get a Global Entry Card. It’s the best $100 I ever spent.