Added documentation for app.paths

changes/1569.feature.rst

@@ -0,0 +1,3 @@
+Corrected line length
+Changed definition listed for cache and toga properties
+Updated formating to use ReST styles

core/src/toga/app.py

@@ -19,7 +19,6 @@
     # Backwards compatibility - imporlib.metadata was added in Python 3.8
     import importlib_metadata
 
-
 # Make sure deprecation warnings are shown by default
 warnings.filterwarnings("default", category=DeprecationWarning)
 
@@ -321,7 +320,7 @@ def __init__(
 
         # Get a platform factory, and a paths instance from the factory.
         self.factory = get_platform_factory()
-        self.paths = self.factory.paths
+        self._paths = self.factory.paths
 
         # If an icon (or icon name) has been explicitly provided, use it;
         # otherwise, the icon will be based on the app name.
@@ -349,6 +348,29 @@ def __init__(
     def _create_impl(self):
         return self.factory.App(interface=self)
 
+    @property
+    def paths(self):
+        """
+        Paths for known safe system locations. Using paths makes sure you have a consistent and known location to store
+        files for your app. Also, some platforms do not allow arbitrary file access to any location on disk.
+        On Android, there are many limitations when it comes to accessing file locations and the apis
+        you can use to read from those locations.
+
+        :PROPERTIES:
+            * **app** – Location of where the apps code is run.
+
+            * **data** – System appropriate location to store user data.
+
+            * **cache** – File location for temporary files that may be removed by the system or user and
+                can be obtained again by the program.
+
+            * **logs** – Location of toga log files.
+
+            * **toga** – Location of the Toga core module.
+
+        """
+        return self._paths
+
     @property
     def name(self):
         """The formal name of the app.