GeometryHUD

If you have a trigger item in the inventory, display the information corresponding to the item.
It improves the gaming experience just a little bit more than using F3(meta-function).

|Trigger Item|Information|
|-|-|
|compass|direction + respawn direction marker|
|lodestone compass|direction + lodestone direction marker|
|recovery compass|direction + last death direction marker|
|clock|in-game time|
|one of compasses + clock|coordinates + in-game time|
|map|mini map|
|spyglass|health gauge of mob|
|daylight detector|in-game days|

These trigger items can also be placed in bundles, shulker boxes, enderchest.