I'm pretty sure you're wondering that too. Yesterday Google pushed out a sneaky little silent update via Google Play Service. I'm a little uneasy about Google doing this, as my phone is no longer really "my phone" especially how they're able to on custom roms such as Cyanogenmod also.
They've also got the ability to remove "malicious" apps from your phone too, but let's just hope they're only malicious ones. Google does no evil right? Hmm, haven't heard that in a while. Oh well.
The app itself doesn't really seem to do much other than allow you to see which apps are using your G+ login details.
Some people are saying it's going to be built into Android 5 (Key Lime Pie) and this is just temporary. But if you have no use for it, feel free to remove or archive it away using your favourite usual app backup tools such as Titanium Backup or File Expert.
Damn you Google, I thought you were better than that. Most other updates like the Play Store usually have a notification of sorts.
But alas, all our complaints are just gonna get stone-walled.
On a side note, at least now we know there are backdoors into all the phones with the Play Store ;)
- CNET: Explaining the Google Settings icon on your Android device
- Android Central: About that Google Settings app that appeared on your device today
- xda-developers: "Google Settings" app just appeared on my phone!!
- The Verge: PSA: A mysterious Google Settings app may soon appear on your Android device