Samsung galaxy A series
if got more budget get the S series
mobile payment just keep to one phone ho liao,
or use the 2 bank acc, one for saving, one top up for mobile payment only, tio hack or whatever only small amount loss.
get new model phone since old model they gonna drop OS support/update... banking app will eventually drop support for old model too.
if phone prompt for OS software update, security update, let your phone update it.
if your phone install app that is not from google store one... bank app probably will flag a warning.