As we patiently await an update to make WhatsApp support native display sizes of the iPhone 6 and iPhone 6 Plus, the tremendously popular Facebook-owned messaging service on Wednesday enabled a new check mark in the chat UI indicating that the recipient has read your message.
Now when you're chatting with someone, pay attention to read receipts in the form of blue check marks, as discovered by designer, Dutch translator at Twitter and jailbreak developer Timon Olsthoorn (and many others on Twitter).
This is an over-the-air update so those with WhatsApp installed on their iPhone can start using this feature immediately, without the need to update the app manually.
WhatsApp, which has more than 600 million active users, is free in the App Store.