# Riley Testut

> Riley Testut is an American indie iOS developer best known for creating GBA4iOS, Delta, and AltStore - tools that collectively redefined what's possible outside Apple's walled garden. Starting at age 13 with a Game Boy emulator built from scratch using Microsoft Paint graphics, Riley spent a decade fighting Apple's restrictions before seeing Delta hit #1 on the App Store in 2024 and launching the first EU-approved third-party iOS marketplace. His work forced Apple to change its App Store rules - twice - without a single lobbyist, just relentless building.

- **Role:** Co-founder & Developer at AltStore / Creator of Delta
- **Organizations:** AltStore, Delta
- **From:** Dallas, USA
- **Nationality:** American
- **Education:** B.S. Computer Science, University of Southern California (USC), Viterbi School of Engineering, High School Diploma, Richardson High School
- **Known for:** GBA4iOS downloaded 10+ million times with no App Store presence and no charge, Delta reached #1 on iOS App Store charts in May 2024 - a 10-year journey from concept to chart-topper, Launched AltStore PAL - the first EU Apple-approved third-party iOS marketplace (April 2024)

## Career timeline

- **2009** — Released first app 'Shoot Around' at age 13, graphics made in Microsoft Paint
- **2012** — Released GBA4iOS v1 on GitHub - Game Boy Advance emulator for non-jailbroken iPhones
- **2013** — GBA4iOS went viral, covered by Time Magazine; Twitter following exploded
- **2014** — GBA4iOS 2.0 launched during film class - downloaded 10M+ times; Nintendo DMCA issued; Apple patched the loophole in iOS 8.1
- **2014** — Enrolled at USC; began developing Delta as a Swift learning project
- **2015** — Won USC WebReg app competition as a CS freshman; Apple rejected Delta from App Store
- **2016-2018** — Interned at Bottle Rocket Studios; Lead iOS Developer at Ponder (social app)
- **2018** — Graduated USC; began working on Delta full-time supported by Patreon
- **2019** — Launched AltStore - alternative app store for iOS using legitimate Apple developer sideloading
- **2020** — Released Clip - background clipboard manager; launched AltJIT for JIT compilation support
- **2021** — Delta 1.3 added Nintendo DS emulation
- **2024** — Delta approved on App Store (April 17) - hit #1 chart; AltStore PAL launched in EU as first Apple-approved third-party marketplace
- **2024** — Forbes 30 Under 30 (Games category) for 2025 list; Delta first U.S. app with External Purchase Link Entitlement
- **2025** — Delta 1.7 launched Nintendo DS online multiplayer; Delta Camera app released
- **2025** — AltStore PAL raised $6M from Pace Capital; converted to Public Benefit Corporation; joined Fediverse; donated $500K to open-source social web

## Achievements

- GBA4iOS downloaded 10+ million times with no App Store presence and no charge
- Delta reached #1 on iOS App Store charts in May 2024 - a 10-year journey from concept to chart-topper
- Launched AltStore PAL - the first EU Apple-approved third-party iOS marketplace (April 2024)
- Forced Apple to change App Store rules to allow emulators (April 2024) and virtual machines
- Forbes 30 Under 30 - Games category, 2025
- Raised $6M from Pace Capital while retaining Delta entirely and converting AltStore to a public benefit corporation
- AltStore Patreon earned over $13,000/month - community-funded for 5+ years before VC investment
- Won USC WebReg app competition as a CS freshman in 2015
- Delta became first U.S. App Store app to use Apple's External Purchase Link Entitlement (December 2024)

## Latest updates

- **2025-10** — AltStore PAL raised $6M from Pace Capital, converted to Public Benefit Corporation, joined Fediverse, donated $500K to open-source social web projects
- **2025-06** — Delta Camera released - standalone app mimicking the Game Boy Camera aesthetic on iPhone
- **2025-04** — Delta 1.7 launched with Nintendo DS online multiplayer via community Nintendo WFC servers
- **2024-12** — Named to Forbes 30 Under 30 Games 2025; Delta became first U.S. App Store app with External Purchase Link Entitlement
- **2024-04** — Delta officially approved on App Store; AltStore PAL launched as first EU Apple-approved third-party marketplace
- **2024-05** — Delta reached #1 on iOS App Store charts

## Links

- Website: https://rileytestut.com
- LinkedIn: https://www.linkedin.com/in/riley-testut-77931634/
- Twitter/X: https://twitter.com/rileytestut
- GitHub: https://github.com/rileytestut

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Profile page: https://yespress.io/riley-testut
Published by YesPress — https://yespress.io
Last updated: 2026-04-25