Today I was walking on Remegio Crespo when a couple asked me if I knew my way around. They asked me where La Fornace Restaurant was located. They were tourists from Idaho and we quickly found a common ground since my wife is from Idaho. I told them that the Restaurant was about 3/4 mile away but that I thought they could get a better meal at Tutto Matto. I didn’t know if the Restaurant was open so I took out my Nexus 5 and said “OK Google” (The Android Personal Assistant). I then asked the personal assistant if the Restaurant was open. It took me to Tutto Matto’s Facebook Page and we all found out that the Restaurant was closed on Monday. “Wow” was the reply of the tourists. Google Now works in Ecuador- unfortunately Siri the personal assistant on the iPhone does not work with the maps section of Ecuador.
Siri does work very well with commands like setting alarms, sending texts, finding songs etc. I find that Google Now works much better with informational items like “What is the name of the Secretary of State Of the U.S.”
Cortana is the name of the Personal Assistant on the Windows Phone but I have no personal experience against Siri or Google Now.
A lot depends on the noise level of the street when using your Personal Assistant but I find Google Now invaluable in a quiet setting when I need instant information.
You can see a CNET Video of Sir and Google Now compared here