Eyes are used to find Dimensional Strongholds and Static Portals. Not all crafting recipes are confirmed yet, but their basic controls are thought out. To use an Eye, simply right click. It will float into the air and release particles that fly towards the Dimensional Stronghold. After which, it will drop back to the ground. Eyes are used to activate Static Portals. Each static portal requires 12 eyes by default, however some eyes may already be placed in.
Pearls are throwable items that are the main crafting ingredient to create the Eyes of their respective dimension. They also allow for quick travel via teleportation, so long as you are in it's respective dimension. If you attempt to use one outside it's respective dimension, it will not work. Crafting recipes are still in progress, but all Dimensional Pearls require at least one Ender Pearl as a base. Ender Pearls are found in the Overworld, but it is currently being discussed whether Endermen should spawn in all dimensions.