Online status is handled by something Spiegel calls "Here" — an idea at the crux of the new Snapchat. At any moment, a blue bubble might subtly appear in your chat window and pulsate softly to let you know that your friend is also in the chat. "The accepted notion of an online indicator that every chat service has is really a negative indicator," says Spiegel. "It means ‘my friend is available and doesn’t want to talk to you,’ versus this idea in Snapchat where ‘my friend is here and is giving you their full attention.’" Only when both people are inside a chat can they initiate a video call by pressing and holding on the blue button.

But video chats don’t have to go both ways. When you tap and hold on the blue button, within a couple seconds your face lights up on your friend’s screen. There’s no ringing, and there’s no "answer call" button to press. You can talk as much as you want while your friend listens, and if you want to show them something you can drag your finger upwards to activate your rear-facing camera. If your friend wants to join in, they can tap and hold on their screen to start sending video your way. There’s no "end call" button either, naturally. You just lift up your finger.

"Ideally you have these serendipitous moments where you and I are both available at the same time," says Spiegel, but how often will you and a friend be staring at the same chat window? Perhaps more often than you’d think, thanks to one of Snapchat’s most interesting new innovations — its typing indicator, or lack thereof. Spiegel describes a scenario where you start typing an iMessage, then see that your friend is also typing, so you stop, and then they stop. It’s like bumping into somebody in the hallway and juking back and forth, unable to pass. The "Here" indicator solves this problem, Spiegel says, but what if you still want to know when a friend’s ready to chat? Instead of using in-app typing indicators, Snapchat sends a push notification to your lock screen to say that a friend has begun typing a message to you. The hope is that by the time they hit send, you’re already in the chat, ready to respond or video chat with them.

Spiegel and co. also took the opportunity to cut down on the incessant text notifications many of us experience. The new Snapchat only buzzes your phone once, no matter how many times a friend texts you in a row. Also, while you’re video-chatting with a friend, your own portrait eventually fades into the background to avoid distracting you. These choices are some of the most deliberate inside Snapchat, but are broad enough in principle that you could imagine other apps picking up on them, much as they cloned Snapchat’s disappearing messages.

Spiegel’s refusal to abide by conventional notions of calling, texting, or sending a photo would seem naive if Snapchat weren’t such a runaway success. The app convinced tens of millions of people to share more photos than they ever had by stripping down conventions about how sending an MMS should work. Today, with just a fraction of Facebook’s user base, Snapchat users share more photos per day than Facebook users. Snapchat claims that over 700 million snaps are shared per day on the service, which could make it the most-used photo-sharing app in the world — ahead of Facebook, WhatsApp, and others. Even Snapchat’s Stories feature seems to be doing well, amassing 500 million views per day.

However, upending the mobile photo-sharing space seems simple in comparison to changing a person’s texting habits. Services like WhatsApp, Skype, and iMessage have hundreds of millions of active, loyal users who text and video call each other every day. Does the new Snapchat offer enough of an incentive to switch? When people want to have a conversation with a friend, will they tap on Snapchat, or on their messaging app? "If we can always try and emphasize how important it is for both people to be [in a conversation] at the same time, that would be a win for us — that would be the holy grail," says Spiegel. "This captures the best parts of a conversation, that you and I are here, we’re both paying attention to each other, and that feels good."