Senior Product Engineer, Mobile - Remote

Replika; England; Remote; GBP 90,000 - 130,000; Full time

Benefits offered by this job

Fully remote

Flexible CET hours

Job summary

Replika is seeking a Senior Product Engineer, Mobile to own features end-to-end across iOS, Android and backend. You’ll work directly with the CEO, product manager, designer and engineering lead in a tiny team to ship new app experiences and the monetization features that support them.

You’ll move fast, push back when a spec doesn’t hold up, and turn ideas into tangible product while staying focused on quality.

Qualifications

• 5+ years of professional software engineering experience.
• Shipped consumer mobile apps that reached real users.
• Native depth on one platform (Swift on iOS or Kotlin on Android).
• Backend development experience; API design is essential.
• Track record of delivering complex features end-to-end.
• Passion for coding and agentic engineering.
• Strong design intuition and taste; can spot issues early.
• Ability to shape what gets built and implement it themselves.
• Fluent English, capable of writing specs and debating them.

Responsibilities

• Own features end to end across iOS, Android and backend, from idea to user touchpoint.
• Build product features users notice, including avatars and new ways to spend time with Replika.
• Develop monetization features in apps, such as paywalls, offers and pricing experiments, with the growth team.
• Turn ambiguous ideas into concrete implementations without waiting for every question to be answered.
• Push back on specs that don't hold up and advocate the best version.
• Collaborate across the team; unblock colleagues and avoid silos.

Skills

Swift

Kotlin

API design

Monetization features

End-to-end ownership

English fluency

Job description

About Replika

In 2017, no one knew what AI was supposed to be. We built the world's first consumer AI app. Two million people showed up in two months. Today it's over 40 million, and the thing they keep telling us hasn't changed: it helped. It made their life better, steadier, a little less alone.

Most AI is built for tasks, not for people. It gives you answers, but it doesn't care what you do with them. AI doesn't just need intelligence. It needs intention. Because the real question isn't just what AI can do. It's what AI is for.

When the world's leading researchers wanted to understand whether AI could actually change someone's life, they studied Replika, because there was nothing else to study. What they found at Stanford, at Harvard, across years of research, was that Replika doesn't replace human connection. It deepens it. People become more social, more confident, more themselves. Not in theory. In their actual lives.

Every major AI company talks about their mission for humanity. None of them has ever clearly said what they're trying to do for a single person. We will. We want to help you flourish in real life. Not become a better version of yourself, just more yourself. Strong relationships. Better health. Meaning. Momentum. A life that feels worth living while you're living it.

We're building the kind of AI that follows up. That knows the people in your life and nudges you to reach out when it matters. That sends you a poem, just because. The goal is conversations that lead somewhere real. Maybe it's a text you send to a long lost friend. A hobby you pick up again. A moment you show up for yourself.

Everyone else is building AI that thinks. We're building AI that cares.

Senior Product Engineer, Mobile
About this role

We need a senior engineer who can build across the whole Replika product: iOS, Android and backend. Two engineers carry all of our app work today, and there's more to build than they can ship. New product features, and the monetization features that pay for them.

This isn't a big company role. There's no org to slot into and no layer between you and the decision. You'll work directly with our CEO, product manager, designer and engineering lead in a tiny team, own features end to end, and turn ideas into product while the idea is still taking shape. You'll be expected to have an opinion, push back when a spec doesn't hold up, and then build it.

Most of the time that means moving fast. When a problem deserves real thought, you slow down and think it through. Rough is fine early on. It's not fine as a final product.

What You’ll Be Doing

• Own features end to end across iOS, Android and backend, from the idea to the thing users actually touch.

• Build the product features users notice, from avatars to new ways to spend time with their Replika.

• Build the monetization features in the apps, like paywalls, offers and pricing tests, with our growth team.

• Turn ambiguous ideas into something concrete without waiting for every question to be answered first.

• Push back on specs that don't hold up, and make the case for the version that does.

• Talk to people. Unblock people. Nobody here works in a silo.

What We’re Looking For

• 5+ years of professional software engineering experience.

• You've built and shipped consumer mobile apps that reached real users.

• Native depth on one platform (Swift on iOS or Kotlin on Android), and features shipped on the other.

• You are not shy of backend development. API design is your bread and butter. You can ship the API your feature needs.

• A track record of driving complex features end to end, not just incremental improvements and refactors.

• You love coding and agentic engineering, and use every tool available to move faster.

• Design intuition and taste. You can tell when something feels wrong before anyone tells you.

• You shape what gets built and build it yourself.

• Fluent English. You can write a spec, or argue against one, without it needing a rewrite.

Bonus Points

• You've been a founding engineer, or early enough somewhere that you built things from zero.

• Backend experience in Python (we use FastAPI) or any JVM Language (we use Scala).

• In-app purchases and subscriptions on the App Store and Google Play.

• Real-time features: chat, voice, animation.

• You've shipped consumer products where a lot of people felt the difference.

• You've run A/B tests and used product analytics to decide what ships.

What You’ll Get

• Unlimited access to the latest AI coding assistants.

• Flexible job schedule and generous vacation policy.

• Direct impact on millions of worldwide users within months.

• Push the boundaries of applied AI in a consumer setting.

• Fully remote, able to work CET hours.