Yeah. I mean you can probably stand in other squares I assume and it would probably be fine but this square I assume is the most efficient place to stand.
Err in theory yes but I doubt you want to have the app open for 6 hours at a time. I don't know about you but on my iphone if I have the app closed for more than 5 minutes it logs me out so not recommended.
I do recommend though having this up on your computer and using Chrome Remote Desktop which Yasti mentioned in his original post - I use this of an evening. I leave my computer on upstairs and then just login to my computer from my mobile while watching tv, tap a potion once every 20 minutes:)!