I've used this app for 2-3 years, despite numerous issues:
For example, it seems the app was never updated to properly take advantage of newer iPhone cameras. So the images are formatted improperly. They are also frequently blurry (which did not happen with Sneaky Pix, another app that's since disappeared).
Also, merely launching the app inexplicably causes the iPhone's audio to be turned down to nearly zero. So, if I'm listening to music or to a podcast, launching this app cancels that audio—for no reason whatsoever.
I wrote the developer about this, over a year ago, but never got a reply. And now, the support link in the App Store leads to a defunct web page.
Finally, I just upgraded to an iPhone Xs Max, and Silent Cam is saying it "doesn't have permission" to access my photos. But there's no way to *grant* it permission!
The app needs an update! But the developer is MIA. This is so infuriating.