A Phone Niche
Remember when every house had a landline? Since rotary phones were bulky and wide, some architects build phone niches into the wall. Keep in mind that these phones had cords, so people had to stand around to talk. Hence, phone niches often appeared in hallways, kitchens, and bedrooms.
Many homes still have phone niches tucked into the wall. If you have a landline, you can store it there as the developer intended. Others use their phone niches to hold mail or display decorative plants.