my cheep $100 TCL A30 phone screen always turned dark after calling someone + now its very dim + barely unreadable when i turn the phone on. not a phone guy + only use it lightly + have AirVoice an MVNO which worked good enough for me on the cheep!! just happened yesterday when i was trying to learn how to send a pic + was also "cleaning out" disabling stuff not needed, would not the first time i "messed" up while trying to improve + learn! suggestions appreciated.