The new update brings a trick to using a different font. The new WhatsApp update allows you to change the font. The "retro" style font in question is called FixedSys and is very easy to use: just type three inverted single quotes at the beginning and end of your message ("`). This replaces the default Helvetica font.
This character is found on the symbols keyboard on Android devices. On iPhones it is a bit more complicated: it is not included by default. To get the backtick you have to download a different keyboard from the App Store.
WhatsApp had already included ways to use bold, italics and strikethrough in messages
Source: chrome
