get a look at following guide to know how to root T-Mobile's S7 and S7 edge
here is a list of some decent cases you can already grab - https://phonendustry.com/best-cases-for-galaxy-note-9-round-up/
I think this list might help for grabbing a OnePlus 6 battery case
roundup of battery cases and chargers
Similar to the previous threads for OnePlus 5 or OnePlus 5T, here are the necessary packages to unbrick/revive a hard bricked OnePlus 6.
For detailed procedures, please consult...
check official amazon page of Samsung