I just purchased a 2014 Prius v three. If my car is locked, should I be able to open the back door if the smart key is in my pocket?
You can setup so the key free opening of the driver's side opens all doors. From outside of the car with it off, press UNLOCK and LOCK for 5 seconds. It will be in all door unlock from driver's side. Repeat to return to only the driver's door unlocks.
You can also set up so touching fob once opens the drivers door or opens all doors. This is from a 2012 but your 2014 will be similar http://www.toyota.com/t3Portal/document/omnav/OM33A02U/pdf/n08.pdf (page 16 of the PDF)