Recompiling existing working Android app with 5.5.1 resulted in QSettings returning status() == 1 and isWritable() == 0.
The usage is basic, QSettings s; s.setValue(); s.sync();
Same code works fine with 5.4.2.
iOS works fine.
The file name used by default for user settings is incorrect in 5.5.1 for Android,
settings.fileName() reports "/.config/uCampaign/uCampaign.conf"
while 5.4.2 settings.fileName() reports "/data/data/com.ucampaignapp/files/.config/uCampaign/uCampaign.conf"