The app in question is the Galaxy S7 Secure Folder app that is actually available for download at the moment. The app has yet to be released officially but for those who downloaded the APK, it seems that upon installing the app for the first time, a render will pop up (see above) which tells you how to use the app, and it also shows the image of a phone that they have speculated could be the Galaxy S8.
The rendering of the phone inside the app certainly looks very familiar and is in line with the leaks that we saw earlier, so it is possible that they could be the same device. However it is odd that the Galaxy S8’s design would pop up in an app that was designed for the Galaxy S7, unless of course there are plans to bring the app onto the Galaxy S8 as well.
Assuming these renders are real, it looks like some of the rumors about the Galaxy S8 could be true, which is that it will have pretty thin bezels and that it will be doing away with the home button, but until then we guess it’s best to take it with a grain of salt.