Well I know this is an old thread but I installed Inbox by Gmail(a billion times better, the bundling works well, though it doesn't instill my own privacy confidence when the AI can determine the type of email by content so well but such is life with Gmail, since they're doing it anyway, might as well make it work for me.) You can add pop/IMAP accounts to Inbox, though I don't, because I don't need more data mining, I use goog enough as it is, but useful for old outlook accounts I use for spam or questionable websites
For other concerns about privacy:
-There are multiple individual "app lockers" if you want a lock on your photos or individual apps as opposed to the whole device
-For private browsing:
Firefox/Tor network offer Orfox for Android(I've run it on MM and now Nougat), but you need Orbit and Orfox to run it and anyone who knows Tor knows it can be notoriously slow...
-so a lightweight alternative is Ghostery, a good browser which allows you to even opt-out of data it collects for dev and I've found it to be a useful and fast. I use Firefox sometimes too but Ghostery tends to use less battery and faster.
-For YouTube content I don't need in my history I run it in Ghostery, however I tend to use native YouTube because I'm not really ever viewing anything restricted, if I do then I switch it, and I have YT Red so I don't have to watch commercials for a damn clip.(YT Red- I don't get it-why not just charge for no ads instead of hiding it in a Google music subscription?
)
-Don't even use native email apps, wouldn't add my encrypted email accts to my phone, I wouldn't recommend anyone else doing it either, unless you have separate devices for work and play, and never, ever, log into Google or any social media on your 'work' device, even then I would still root it, enable dev options, install apk direct from source (use OTG or secure private network to transfer whatever you will need but still know accessing anything over wifi or mobile networks is penetrable, best you can hope for is good encryption, even still, living in the US, Mother Russia's powerbottom will be sworn in the next 36 hours so I'm in yet another existential crisis)
-Another handy app for anyone annoyed and worried with how much data average apps collect, is Xprivacy, which has worked on KitKat, Lollipop, and Marshmallow, but I've always used on rooted devices. When apps don't allow you to opt out of an option(what prompted my use was CapOne's lovely addition that demands permissions to make/receive calls and phone # info(some other banks have begun it too but most still allow an opt-out) or it kills the app-yea, sure, it's a "safety" future, I'm sure a bank/lender would NEVER use that info for nefarious reasons
), anyway Xprivacy works by feeding fake or no information, so you can still use a convenient app and so far it's been useful.
If anyone has thoughts on FACEBOOK privacy though- I'll take them. I HATE Facebook, messenger, instagram and all that data it collects and mines. Unfortunately a large amount of my friends use it for almost everything, and the Messenger mandate is even worse, every time I get on to check anything I get someone messaging me, and if I uninstall it I can't see messages, and not being able to get on without others seeing the exact minute I was last active and heaven forbid I leave location on, then geo-tagging, yay!
Right now I'm feeling out some Facebook/messenger wrapper apps, admittedly they are sparse, and I might just buy the only app I could find which allows you to modify fb privacy(last active, message seen/unseen etc)
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