Murmu

Share your thoughts quietly. Murmur your mood and daily vibes to close friends. Just emoji replies, no pressure.

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Inspiration

Murmu was born from a simple feeling: sometimes we want to share a fleeting thought, an emotion, a moment, but it doesn’t feel "important" enough for a full post or a message. Existing platforms are too loud, too performative, or just too much. We wanted a space that felt light, cozy, and low-pressure. Something in between a journal and a chat.

What it does

Murmu is a tiny social app where you can post “murmurs”, short thoughts accompanied by a mood emoji. You can:

  • Write murmurs quickly
  • Pick a mood to go with it
  • See your friends’ murmurs in a soft, emoji-filled feed
  • React with a quiet emoji — no public comments or likes
  • Track your own moods over time in a monthly calendar view

It’s meant to be casual, quiet, and honest.
No pressure to be interesting. Just... say how you feel at that moment.

How we built it

Murmu is built in Swift, with Firebase powering most of the backend. We use:

  • Firebase Auth for Sign in with Apple & Google
  • Firestore to store murmurs, user data, and friendships
  • Cloud Functions (Python) to send push notifications when friends post
  • OneSignal to deliver the actual push
  • RevenueCat to manage subscriptions and entitlements

Challenges we ran into

As an engineer, UI design isn’t usually my comfort zone, but for Murmu, I really wanted it to feel cozy and gentle. I spent a surprising amount of time fine-tuning the interface: choosing the right emoji size, spacing, colors, and how the murmurs appear. It took a lot of trial and error (and asking friends for feedback), but I think I finally landed on something that feels “soft” enough to match the mood of the app.

Accomplishments that we're proud of

  • We shipped the app and passed App Store review
  • The app actually feels like what we imagined: quiet, personal, soft
  • Friends who tested it said they started noticing their own emotions more
  • We kept the scope small and got it done in a few weeks

What we learned

  • Minimal can be powerful
  • People want low-effort ways to stay in touch emotionally
  • Building something small is still really hard, but really satisfying

What's next for Murmu

We have lots of ideas we’re excited to explore next:

  • Smoother and more intuitive friend-adding flow
  • Support for custom emoji packs ✨
  • Murmurs that expire after 24 hours (for a more ephemeral feel)
  • Ability to post photo murmurs, not just text

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