Some things don't work as a text. A story about your day, the way you laugh at the end of it, the face you make when you say you miss someone. You want to say those out loud. But when you and your partner live seven hours apart, a call means one of you is either half asleep or sneaking out of a meeting.

Pulse is a video conversation you don't have to have at the same time. You record a short clip and send it. Your partner watches it when they're free, then records one back. Back and forth, like a call that stretches across a whole day.

How a conversation goes

You open Pulse and record. Before you send, you can watch it back and retake it if you want. The screen tells you when the other person is likely to see it: "Lucía sees it when free — it is 9 PM in Madrid."

When Lucía opens Pulse, your clips play one after another in the order you sent them, so three short videos play like one longer message. When she reaches the end, the app tells her she's caught up: "That was the last one. Your turn to send something back."

A clip from Lucía, with what she says subtitled in your language
A clip from Lucía, with what she says subtitled in your language
Photos sit in the conversation too
Photos sit in the conversation too
So do short notes: translation on top, her original underneath
So do short notes: translation on top, her original underneath

That's the whole idea. There's no feed to scroll, nothing to like. It's a conversation where each of you takes a turn when you have a minute.

The translation is in the subtitles

Here's what makes it work across languages. When Lucía records a clip in Spanish, Heartline transcribes what she says and translates it, and you watch her with subtitles in English. You hear her actual voice and see her actual face, and you still understand every word.

Her clip reaches you once its subtitles are ready, which takes a few seconds, so you never get a video you can't follow. Tap the subtitles to read the full text, or switch to the original if you're practicing her language.

This is the part that's hard to get any other way. Voice notes in a language your partner doesn't speak are just sound. A video message with real subtitles is something they can actually reply to.

Knowing when they're there

At the top of Pulse you can see what your partner is doing: "Watching your clip," "Recording a reply," "In Pulse," or "Away." It's a small thing that makes an asynchronous conversation feel less like sending a message into the dark. If you see "Recording a reply," you know one is coming.

Not just video

Sometimes you don't want to be on camera. The plus button adds a photo or a short text card to the same conversation instead. Text cards are translated for your partner automatically. Photos and cards stay on screen for ten seconds as the conversation plays, then it moves on to the next one.

Where it fits

Pulse is for the in-between: a story from the walk home, a clip of the view from your office, a sleepy "good morning" recorded at their midnight. For the long talks there are live-translated calls. For something waiting when they wake up, there's Morning Moment. And if you're managing a big time difference, our long-distance guide covers how couples combine them.

Heartline provides real-time translation for text, voice, and video calls — built specifically for cross-language couples. Available free on iOS and Android.