Actually, all the Google apps are also inconsistent. I'd rather not go into details though. But some highlights are the drawer that opens from the left look different in all Google apps and and and also that you can't swipe left and right in Google+ when viewing a profile but you can swipe left and right in youtube
Why would two different apps, which serve completely different purposes with completely different functions necessarily be designed exactly the same?
How is that any different from complaining that iOS sucks because Safari has tabs and mail doesn't?
Want to talk about inconsistent? Why do some apps in iOS keep their settings in the system settings, some are in-app and some have both?