iOS Software Engineer

ActAI; Greater London; On-site; GBP 70,000 - 110,000; Full time

Job summary

ActAI is seeking an iOS Software Engineer to own the iOS client experience, shaping how AI feels, responds, and performs in users’ hands. You will build a production-grade iOS application where AI interactions are central to the product experience, prioritizing performance, reliability, and user trust.

The role focuses on delivering responsive, low-latency experiences with memory-efficient code, integrating AI features via backend APIs, and collaborating with ML/Backend teams to evolve the

Qualifications

• 3+ years of iOS development with Swift.
• Hands-on experience integrating AI-powered features into mobile apps.
• Strong understanding of async/await, concurrency, and background tasks.

Responsibilities

• Build and maintain iOS applications using Swift and SwiftUI.
• Integrate AI-powered features through backend APIs.
• Design UX patterns for AI interactions, including loading states and streaming responses.
• Optimize performance, memory usage, and battery efficiency.
• Capture user signals and feedback to support AI evaluation and iteration.
• Collaborate with backend and ML engineers on API design and system behavior.

Skills

Swift

SwiftUI

Async/await

Memory optimization

iOS development

AI integration

Tools

CoreML

TensorFlow Lite

Remote/config flags

Job description

There are over 5 billion users using basic applications today such email, notes, tasks, calendar and they're not AI-native. Our mission is to build proactive applications for anyone in the world, who are not used to complex prompting. We aim to bring intelligence to conversations, errands, organising and workflows, with minimal prompting.

Our product focuses on achieving high reliability for long-running workflows, persistent context, and real-world task completion. We believe products will greatly reduce hallucinations

Our objective is to organise anyone's life, allowing us all to spend time on valuable and meaningful things

Role

As an iOS Software Engineer, you own the iOS client experience, how AI feels, responds, and performs in users’ hands. This is not a thin integration role. You will build a production-grade iOS application where AI interactions are central to product experience, and performance, reliability, and user trust are critical.

Focus

• Build and maintain iOS applications using Swift and SwiftUI.
• Integrate AI-powered features through backend APIs.
• Design UX patterns for AI interactions, including loading states, streaming responses, retries, and fallbacks.
• Optimize performance, memory usage, and battery efficiency.
• Capture user signals and feedback to support AI evaluation and iteration.
• Collaborate closely with backend and ML engineers on API design and system behavior.
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• Maintain high App Store quality, stability, and production reliability.

Ideal Experiences

• 3+ years of iOS development experience using Swift.
• Hands-on experience integrating AI-powered features into mobile apps.
• Strong understanding of async/await, concurrency, and background tasks.
• Solid iOS performance and memory optimization skills.
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• Experience shipping and maintaining production iOS apps.
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• Comfort designing for latency, partial failure, and non-deterministic AI behavior.
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• Exposure to CoreML or light on-device ML.
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• Familiarity with feature flags or remote configuration systems.
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• Strong intuition for AI UX patterns and user trust considerations.

Outcomes

• Stable, smooth, and reliable real-world use iOS applications.
• Performance is optimized: responsive, low-latency, and efficient on memory and CPU.
• Production issues are detected early, monitored effectively, and resolved with clear root-cause analysis.
• Swift
• SPM
• SwiftUI
• SQL / noSQL
• TensorFlow Lite (on-device inference)

How We Work

The best products today in the world were built by small, world class teams. We are a high talent density and hands-on team. We make decisions collectively, move at rapid speed, striking a balance between shipping high quality work and learning. Joining our team requires the ability to bring structure, exercise judgment, and execute independently. Our goal is to put in hands of our users a truly magical product

If there appears to be a fit, we'll reach to schedule 3, but no more than 4 interviews.

Applications are evaluated by our technical team members. Interviews will be conducted via virtual meetings and/or onsite.

We value transparency and efficiency, so expect a prompt decision. If you've demonstrated the exceptional skills and mindset we're looking for, we'll extend an offer to join us. This isn't just a job offer; it's an invitation to be part of a team that's bringing AI to have practical benefits to billions globally.