Added App Permission section to Readme (#215)

README.md

@@ -73,6 +73,12 @@ Many tools are available.
 - Install the certificate in `Trusted Root`.
 - Double click the *.msixbundle file.
 
+## App Permission
+
+DevToys works entirely offline, meaning that none of the data used by the app goes on internet. However, the app requires some other permissions in order to work correctly.
+1. `Uses all system resources` - This permission is required for some tools like `PNG / JPEG Compressor` or (upcomming) `On-screen color picker / measurer`, which use a 3rd part Open-Source Win32 process like [Efficient-Compression-Tool](https://github.com/fhanau/Efficient-Compression-Tool).
+All the code requiring this permission can be found [here](https://github.com/veler/DevToys/tree/main/src/dev/impl/DevToys.OutOfProcService).
+
 ## How to run DevToys
 
 ### Using Start Menu