This addon shows two windows when inspecting a unit.
The first window shows the items so you can keep inspecting them even if the target goes out of range. These are clickable for dress-up, just like the normal Inspect window. As long as the inspected player is your target these are also updated when the target switches gear.
The second window shows a list of stats that are found on the items, which is a total for all items. This list is also updated when the target switches gear. The colored numbers in parentheses is the difference between your gear stats and that of the inspected player. Red means your gear has less of this stat, green means you have more of this stat.
The last inspect data is saved even after logging off and can be shown again by typing /ig. You can delete this saved data by Ctrl-Right-Clicking on the Item window title-bar.
In addition, there's an Inspect button positioned left of the targetframe (standard WoW UI ofcourse, i don't know where it will appear for modified UI's). If you use this button, the standard WoW Inspect window won't even show up. However, if you use the Inspect option from the targetframe menu, the InspectorGadget window will also appear.
When you enter an instance, InspectorGadget will inspect the items of your party members without directly showing anything. When you target a player that is part of your group, the window will show that player's items. This data can also be retrieved after you have left the instance by clicking on the cogwheel button at the top-right of the Items window. This data can also be deleted by Alt-Right-Clicking the Items window title-bar.
1) Auto-showing the last inspect data on login or entering world is intentionaly not done, because sometimes the WoW-client will give an error while loading (the one where you get the choice of 'Sending' a report). Dunno why, but it does. I tested it and it only does that when i try to show the last inspect data on login. To show the last inspect data just type /ig.
2) Unfortunately, not all stats can be collected. Gem and enchant stats can not be found. I've tried to get Gem and enchant stats, but i've been unable to find anything related to this. For this reason, please take the stats list window only as a casual reference, do not assume it is 100% correct.
3) Auto-Inspecting party members doesn't seem to work all the time. Sometimes there isn't a single item received for a player. Have not been able to figure out why.