Important notification about random apps, only way to remove notification is to install app

[Android Central Question]

I had a random notification (android communication on lockscreen). It just had an app name. I installed and uninstalled the app. Then I disabled allow installation from uknown sources but 2 days later another important notification appeared. The only way to remove the notifications is to install the apps. They seem harmless and are in google play store (a pedometer and a flashlight so far) but they are not installed from playstore, nor from amazon app store. Any idea what and why is doing that? I only had allowing install from unknown sources on for amazon app store but I forgot to turn it off. Now it appears it makes no difference. Did a scan with mcaffe but it didn't find anything. I got a blu phone if that makes a difference. Thanks!

 

[Tim1954]

Under no circumstances install such apps! Never. Ever. That's the best way to get malware in your phone!
When the popups appear, back out of the screen using home button and reload.
Uninstall all such apps no matter how harmless they seem... Trojans come in those apps.. Perhaps scan the phone with malwarebytes or similar. The popups are just adware but once you agree to install a sideloaded app, you could have anything!