Keycap, The Number "four"
This is a numeric key, which is depicted as: on a square frame, there is an Arabic numeral "4". This button is commonly used in telephones, computer keyboards, or mobile phone dials. This emoji can be used not only to specify the meaning of entering numbers on the keyboard, but also to dial telephone numbers.
It should be noted that in the Facbook and OpenMoji platforms, the depicted background images are black and gray respectively; Au by KDDI and Docomo platforms display white background frames; The Softbank platform shows a red background picture; As for the background frames of other platforms, they are all designed in blue. In addition, the font used for the number "4" also varies from platform to platform. Some platforms' numbers are more formal and correct, while others are more personalized. For example, the numbers on Docomo platform are decorated with two small squares.
