Senior Mobile Engineer for Consumer App
Worldwide
Seeking a Senior Mobile Engineer to develop a polished consumer app for iOS and Android. The role involves building the app from a finished design, ensuring a seamless user experience and high performance. The ideal candidate will have experience in mobile app development, software QA, and iOS development. We're a small founder-led team with a **fully designed, high-fidelity clickable prototype** for a consumer wellbeing app — a daily self-tracking experience with a friendly companion and a supportive community layer. Design, UX, flows, and copy are done. We need an experienced engineer (or a tight small team) to build it properly: native-quality apps, a real backend, accounts with reliable cloud sync, push notifications, subscriptions, and a moderated community. We care about craft, reliability, and trust. This is a long-term build with ongoing work for the right person. ## What's already done (so you're not starting from scratch) - Complete clickable prototype covering ~15+ screens and the full primary flow (onboarding → daily use → community → progress). - Defined visual system, copy/tone, component states, and an animated companion character. - A written product/build brief, data-model starting point, and feature list (shared after a short intro call / NDA). ## Scope of work - Rebuild the prototype as production apps for **iOS and Android** (we're open to React Native, Flutter, or a strong PWA — propose what you'd use and why). - **Backend & accounts:** secure auth, **automatic free cloud backup**, device transfer, rock-solid account recovery. Data integrity is non-negotiable. - **Offline-first** tracking that syncs when back online. - **Push notifications** with *guaranteed delivery* and smart scheduling (reliability is a feature, not an afterthought). - **Subscriptions / in-app purchases** (free trial → paid) via the app stores. - **Community features:** posts, reactions, replies, 1:1 pairing, group rooms, presence, plus **moderation/reporting** and anti-abuse. - An **AI companion chat** (LLM-backed) with strict safety guardrails and content moderation — experience here is a big plus. - Accessibility (dynamic type, contrast, screen readers), analytics, and **App Store + Play submission** including privacy labels and subscription disclosures. ## Must-have experience - Shipped **at least 2 consumer apps to the App Store and Google Play** that you can show us (links + your specific role). - Production experience with auth, cloud sync/offline, and **subscription/IAP** flows. - Push notification delivery at scale. - Clean, tested, documented code and clear written communication. - Comfortable working from a finished design and flagging gaps proactively. - Paywall setup within RevenueCat ## Nice to have - LLM/chatbot integration with safety/moderation. (Our Api keys will be provided for Claude) - Community/social features and content moderation. - Experience with health/wellbeing or other "sensitive audience" apps and the related store-review nuances. ## How we'll work / what we expect - Weekly demos, source in our repo from day one, short written updates, and realistic estimates. - A **small paid trial milestone first** (1–2 weeks, fixed scope — e.g. auth + one synced tracking screen from our design) before we commit to the full build. This protects both sides. - Quality bar: pixel-faithful to the design, smooth animation, no data loss, graceful offline. ## Anti-spam / vetting filters (how we screen) - **Put the word `SUNRISE` as the first line of your proposal.** Generic or templated bids that ignore this are auto-rejected. - Proposals that don't answer the questions specifically, or that paste a portfolio with no relevance to consumer mobile, are declined. - We will **video call** and may ask you to **walk through code you wrote** and explain a tradeoff you made. - The **paid trial milestone** is the real interview — we judge on actual delivered work, not promises. - Red flags we filter out: no shippable app links, can't explain their own past code, vague "we have a team" with no named people, evasive on data-integrity/offline questions, or pushing to move off-platform immediately. ## Budget & terms - Hourly or milestone-based — propose your rate and a rough estimate for the trial milestone. - Long-term, ongoing engagement for the right fit (maintenance + future features). - IP assignment and an **NDA** before we share the full brief and design source.
$3,000.00
Fixed-price- IntermediateExperience Level
- Remote Job
- Ongoing projectProject Type
Skills and Expertise
Activity on this job
- Proposals:20 to 50
- Last viewed by client:2 hours ago
- Interviewing:0
- Invites sent:0
- Unanswered invites:0
About the client
- AustraliaMelbourne2:22 AM
- $223K total spent256 hires, 39 active
- 20,684 hours
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