How do I make the feed button pop up in Minecraft Pocket Edition?

Solution 1:

According to the wiki you can simply hold an applicable food type in your hand and right click the horse to feed it.

To feed a horse, hold a valid food item and right click on the horse. If the food is invalid, the player will simply mount the horse. Horses can only be fed when feeding would have an effect, similar to other animals.

Valid food types are : Sugar, Wheat, Apple, Golden Carrot, Golden Apple, Hay Bale.

EDIT

Just noticed the pocket edition tag.

• For Java Edition (PC/Mac), right click on the horse.
• For Pocket Edition (PE), you move your pointer over the horse and press the Feed button.
• For Xbox 360 and Xbox One, press the LT button on the Xbox controller.
• For PS3 and PS4, press the L2 button on the PS controller.
• For Wii U, press the ZL button on the gamepad.
• For Nintendo Switch, press the ZL button on the controller.
• For Windows 10 Edition, right click on the horse.
• For Education Edition, right click on the horse.

Note : A horse will only eat food if its health bar is down or if it is a baby horse that is growing. If you try to feed a horse otherwise, it will not eat the food.

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