You can't get away with ignoring that message, unless you want the sender to know you're icing them out.
A new feature that WhatsApp slid to iOS and Android users without creating an actual update now shows senders when a message has been read, according to 9To5Mac. Normally, double check marks would indicate that a message had been received, but now, those check marks turn blue when the message has been read.
There have been recent rumors that WhatsApp will be getting Voice over IP capability. Right now, WhatsApp is being advertised as one dollar after a free year of use.
Whatsapp is a messaging app recently acquired by Facebook that Mark Zuckerberg hopes will "bring the Internet to more people."
"I think WhatsApp is going to be the global text messaging platform," Zuckerberg said in September, according to Bloomberg. "I think we're going to have an opportunity for WhatsApp to connect 2 or 3 billion people."