Or in short: how to hide a folder of phones from the Gallery app.
This is done on a HTC One M8, and parts of it requires the HTC File manager.
How to make a hidden folder
This method is perfect when you want to create a folder that’s specifically made to be hidden. This will not show up in Gallery etc and other apps that relies on media scanning. You will need the file manager app to see the content of that folder. And that “show hidden file” is enabled.
It’s pretty easy to do, inside your file manager app you simple create a new folder. BUT: you add a simple point (.) in-front of the folder name. Like:
Which will simply create a hidden folder called “hidden”. When you do this the first time in HTC File manager it will turn on “show hidden file”, so that you can actually see the folder that you creates.