I think Google Now will do the last one for you already (location based reminders). I use it for reminding myself about things when I get to work or home. Just say "Okay google remind me to <thing>" and then there's a location option for when.

I don't own a watch, but I think they probably implement this feature.

Shopping list + location based reminders -> look at Google Keep, it has list integration with the watch + location based reminders :-)