We will have FAQ here and try to answer and place more info over-time.
Why Can't i level up more i am 28?
A. Once you have done all possible quests and catching evomons and cannot reached lv 30 to Ascend,have friends take you to other places to farm new normal/shiny Evomons to get to 30 trainer level and than wait for Daily resets to happen.
WHAT BALL IS USED GOOD?
A. Prismatic ball great for any normal/Shiny but most user's use it on Shiny due to better stats overall.
WHY CAN'T MY FRIEND HELP ME ON DUNGEON?
A.they must not have been Trainer leveled or have quest issued to do that dungeons.