Six to Start

What Six to Start does

Six to Start is an independent game developer founded in 2007 and headquartered in London, United Kingdom, operating with a team of 11–50 employees. The company specializes in narrative-driven mobile applications that combine audio storytelling with physical activity, anchored by its flagship product Zombies, Run! — a zombie-themed fitness app that transforms walking, jogging, and running workouts into immersive audio adventures using GPS tracking, scripted mission briefings, and dynamic enemy-chase mechanics. The product portfolio includes the flagship Zombies, Run! app (500+ missions across multiple story seasons), the Zombies, Run! 5K Training beginner program, and the Venture sub-brand offering sci-fi, fantasy, and horror adventure content, including cross-IP collaborations such as X-Men: Munroe & Wagner.

The company operates a product-led go-to-market model, distributing exclusively through the Apple App Store and Google Play Store globally, with a freemium tier and paid subscription membership for full mission-library access. Revenue is generated through app subscriptions, gift codes, and branded merchandise sales via a direct e-commerce storefront. Marketing relies on app-store optimization, multi-platform social media engagement (Twitter/X, Facebook, Instagram, YouTube, TikTok, Threads), and email newsletters. The company has accumulated 10+ million players and a 4.8/5 App Store rating across 40,000+ reviews, making it the self-described largest smartphone fitness game by player base.

Six to Start was co-created by novelist Naomi Alderman and was previously acquired by blockchain company OliveX around 2021, which had planned to shut down the developer. In November 2025, Alderman exercised a contractual buyback clause to repurchase the Zombies, Run! rights, returning the product to independent founder ownership. The company continues to release new episodic content (e.g., the 2025 'Back From The Dead' 8-mission arc) and operates as a privately held, founder-owned entity with no disclosed institutional investors beyond an early 2017 investment from Nesta Ventures.

Name

Six to Start

Legal name

Six to Start

Website

https://sixtostart.com

Company type

Private

Founded year

2007

Operating status

Operating

Headcount range

11–50 employees

Short description

Six to Start is a London-based independent game developer (founded 2007) that creates narrative-driven fitness mobile apps, primarily Zombies, Run!, a zombie-themed audio adventure with 10+ million users across iOS and Android, monetized via freemium subscriptions, gift codes, and branded merchandise.

Ownership category

akta.pro rank

Product category

Fitness Mobile Apps

NAICS

Sports and Recreation Instruction (61162), All Other Amusement and Recreation Industries (71399)

SIC

Services-Prepackaged Software (7372), Services-Amusement & Recreation Services (7900)

akta.pro primary industry

Online/Remote Personal Training & Programming (HSADAAAM)

akta.pro secondary industries

Endurance & Running/Cycling Training (HSADAAAG), Serious Games & Simulation Studios (Training, Defense, Enterprise) (MPAFAAAH)

Keywords

• Fitness gaming apps
• Narrative workout experiences
• Story-driven running
• Gamified fitness software
• Audio adventure workouts

Headquarters

HQ city

London

HQ country

United Kingdom

HQ region

Europe

Markets served

GTM type

B2C

Offering type

Software

Cost components

Technology or R&D, Personnel, Marketing or Sales, Operations

Revenue model

1. App Subscription (Membership): Subscription-based model providing access to premium story missions, workouts, and exclusive content. Users can purchase individual missions or subscribe for full access.
2. Merchandise Sales: E-commerce sales of branded merchandise including t-shirts, mugs, fitness gear, water bottles, and accessories through the company's own storefront
3. Gift Codes: Digital gift code purchases for memberships, allowing users to gift subscriptions to others

Pricing tiers

Go-to-market motion1 record

Distribution channels3 records

Marketing channels3 records

Core offering

Six to Start develops and publishes story-driven mobile fitness apps that transform walking, jogging, and running into immersive audio adventures. Its flagship product Zombies, Run! gamifies workouts through narrative missions, optional enemy chase mechanics, and a 500+ mission content library, distributed as a freemium subscription on iOS and Android and complemented by branded merchandise sales.

Product overview

Six to Start is a fitness gaming company that develops a portfolio of narrative-driven mobile apps centered on transforming physical exercise into interactive audio adventures. The core product Zombies, Run! uses zombie apocalypse storytelling with dynamic chase mechanics to gamify workouts, supported by a subscription model and available on iOS and Android platforms. The offering includes the flagship Zombies, Run! app (with 500+ missions and 10+ million players), the beginner-focused 5K Training module, and the multi-genre sub-brand Venture featuring sci-fi, fantasy, and horror content. The company operates under a story-driven membership model with merchandise sales complementing the digital products.

Differentiator

Problem solved

Functional benefit

Brands

• Zombies, Run!: Zombie-themed fitness app that transforms workouts into audio adventures with story missions and chase sequences.
• Venture

Products and services

• Zombies, Run!

Quantifiable outcome

• 10+ million players have joined the platform
• +1 more outcomes

Named customers1 record

Segments1 record

Ideal customer profiles1 record

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature4 records

Partnerships

Two partnerships are on record, tiered core.

• Apple (App Store)coreChannel Partner/ Reseller/ DistributorApple App Store distribution partnership for the iOS version of Zombies, Run!, providing access to Apple's subscription services and payment infrastructure
• Google (Play Store)coreChannel Partner/ Reseller/ DistributorGoogle Play Store distribution partnership for the Android version of Zombies, Run!, providing access to Google's subscription services and payment infrastructure

Scale indicators3 records

Recent moves5 records

Expansion highlights5 records

Direct peers

• Aaptiv: Audio-based fitness subscription app offering guided跑步, cycling, strength, and yoga workouts. Directly comparable to Zombies, Run! as an audio-first, on-demand fitness experience sold via mobile app subscription.
• Charity Miles: Free app that turns walking, running, and cycling into charitable donations via corporate sponsorship. Direct peer in the gamified-fitness-for-motivation category, though with a philanthropy hook rather than a story hook.

Broad incumbents

• Nike Run Club: Free Nike-owned running app with audio-guided runs, training plans, and GPS tracking. A broader incumbent in the same running-app category, with vastly larger scale and marketing budget than Six to Start.
• Strava: Dominant social fitness tracking platform for runners and cyclists, with subscription tier. Competes for the same end user (recreational runners) via GPS tracking, community, and challenges.
• Peloton App: Peloton's digital fitness subscription offers audio and video guided runs, strength, yoga, and more. A broad incumbent fitness subscription app overlapping with Zombies, Run! in the audio-guided running category.
• Apple Fitness+: Apple's subscription fitness service with audio-guided walks, runs, and trainer-led content integrated with Apple Watch. A major incumbent in the same audio-guided workout category, with deep ecosystem lock-in.

Emerging players

• Niantic (Pokémon GO): Pokémon GO and Niantic's broader portfolio (Ingress, Pikmin Bloom) gamify walking and outdoor activity through mobile AR. Highly comparable as location-based, story-driven games that motivate physical movement, though using AR rather than audio.
• SuperBetter: Mental wellness and habit-building app using game mechanics (quests, power-ups, allies) to drive real-world behavior change. Comparable as a gameful-design-for-real-world-activity product, though focused on resilience/wellness rather than跑步.
• Fit Radio: Audio fitness app delivering DJ-curated workout music for running, cycling, and gym sessions. Adjacent peer in the audio-driven fitness subscription category, though focused on music rather than narrative.
• Ring Fit Adventure (Nintendo): Nintendo's Ring Fit Adventure gamifies exercise through a story-driven adventure controlled via a fitness accessory for the Switch. Strong conceptual parallel to Zombies, Run! as a narrative gamification of physical activity, though on console rather than mobile.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat4 records

Key risks7 records

Key highlights7 records

Customer concentration

• Xx.com/sixtostart
• YouTubeyoutube.com/@runwithZRX
• Facebookfacebook.com/runwithZRX
• Instagraminstagram.com/runwithzrx
• TikToktiktok.com/@runwithzrx

Revenue estimate

Valuation estimate

Number of profiles

Profiles3 records

Funding overview

Funding rounds1 record

Investors1 record

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Six to Start