+Shows the amount of space used by your apps, according to your most recent backup.
+* Make a proper class for the space-map data
+* Export that class to a dict/json
+* Parse my iTunes Mobile Apps folder and store:
+ * App icon (extract to a folder)
+* Integrate the above data with the space-map-data class
+* Update the tree-map to show that size data (with a 3-way toggle per kind of data)
+* Allow pan/zoom on the TreeMap
+* Consider switching to a different treemap source to make the above easier?
+* Add a "keep/hidden" attribute to remove big-but-want-to-keep apps from the TreeMap
+* Make a "Pile of Shame" queue of apps to keep-or-kill
+* Make a list of apps that aren't installed
+ * Make it a keep-or-delete queue
+* Support reading the Springboard data from a connected iPhone with libimobiledevice?