I don't use auto brightness on any of my phones because I don't much like it, but I I find 40-50% or thereabouts is good in bright sunlight. At say 20-25% it can be difficult even to see the lockscreen keypad for entering the PIN.
My Lumia is set to medium brightness and causes no problems.
Posted via Android Central App
My Lumia is set to medium brightness and causes no problems.
Posted via Android Central App