Various pictures

Hang near your baby bed or an  armchair for feeding some nice pictures, reproductions, photographs or drawings.
Offer your little one to view them. Periodically change the pictures - thus your baby won't loose the interest to looking at the pictures.
For these purposes it is convenient to use a special magnetic board.
Make photos of your baby looking at the pictures and upload to the App. Write what picture is your baby's favourite and describe his/her reaction to it.