With default settings Android is pretty security and can be hardened, viz. BlackBerry betting its business on this.
Can be hardened, yes, sure, but not by you or me.
Android has a disastrous security track record ... some 95% of all Androids on the market are vulnerable to at least one threat which will not be fixed by Google, assuming Oreo has a 5% Android marketshare, I guess much less, but still ...
As for Blackberry ... they have trouble getting updates for their Android phones ... just ended updates to Priv and dtek's
Yes, BB10 fanboy, here ... :'(
BUT, Android sucks, their default mail app is plain useless, YES, useless, a waste of space on the device ... ok, you can get another, but email is kinda central to a phone, up there with texts and calling. Have not seen a decent filemanager on the device, yet. The sound management is a joke, like media/ringtone sound levels - I keep muting my phone when I want to reduce media sound ... I don't want everybody on the train to hear I am about to play CandyCrush, thanks, yet I do want to keep ringtone sound level normal, please ... how hard can that be ? BB10 and iOS do that out of the box.
At least now you can format microsd cards and install apps on them, we are getting there ... only if you get Android 6 (iirc) or later ... 80% of phones out there won't get 6, let alone 7 or 8 ...
Android, to be honest, I cannot understand how they could be where they are ... the OS sucks golf balls through garden hoses ...
Now, Apple, iOS has its problems, too ... no microsd, for example, completely F'd up, Listen, Ive, the 1980's called, they want their lockin back ... iTunes ... (no need to go into that, right ? We all know iTunes sucks), File management on iOS ?
Backups, hm, backups ... So, you have an issue, as in, you cannot install any apps anymore, you have tons of space, but no, it downloads but won't install ... since Apple has this locked-in filesystem BS, you cannot really get off the device what you want to then factory restore it ... no, you put your crown jewels (iow you backup your private data) on ff'ing iCloud, reset the phone, play the backup back and the f*cker still does not want to install apps ... you backed up the glitch ... soooo handy ... what do you do now ? You are AppleFsck'd!
We really need Debian or something on these devices ... these phone OS's are crap!