Google's new research points out the biggest flaw with owning an Android phone
The report says that the security flaws were there because of changes Samsung made to Android. Like most Android phone manufacturers, Samsung modifies Android with customized apps and user interfaces. It's not the same "pure" version you see on Google's own Nexus phones.
And that's the problem. Because manufacturers play around with Android so much, it has the potential to open up even more security holes, just like the ones Google found on the Galaxy S6 Edge.
Plus, it can take manufacturers a long time to patch those holes because of various restrictions from wireless carriers and other third third parties. Samsung was able to fix most of the major problems Google found in the Galaxy S6 Edge, but Google says three other flaws it found remain unfixed.
For even more evidence, look at the Stagefright bug that came to light over the summer. Stagefright was a hole in most Android phones that allowed devices to be taken over simply by receiving a text message. Google pushed out a fix, but most Android phones weren't able to get it.
The biggest problem with owning an Android phone is that you rarely have a guarantee that it'll be supported by critical security updates from the manufacturer, especially when a new hack like Stagefright is discovered. The only way to ensure you're running the latest and greatest version of Android with no compromises is to buy a Nexus phone straight from Google. Nexus phones receive regular, timely updates.
No other manufacturer of Android phones can guarantee that yet.