After Apple loosened its App Store guidelines to allow game emulators, the retro game emulator Delta quickly climbed to the top of the App Store charts. This surge in popularity, however, also drew legal scrutiny from Adobe, which claimed Delta’s logo was too similar to its own.
Delta was developed by Riley Testut, who began his journey into emulation by loading games onto graphing calculators before turning his focus to iOS. Delta evolved from Testut’s earlier app, GBA4iOS, which allowed emulated games to run on iOS devices without jailbreaking. GBA4iOS was immensely popular, attracting millions of users, but Apple eventually shut it down.
With Apple now facing regulatory pressure to allow more competition in its App Store, it began permitting game emulators in April. This change has opened up new opportunities for developers to tap into the App Store’s vast user base. Apple prefers to host these apps rather than compete with alternative app stores that might feature previously banned content.
Seizing this chance, Testut launched Delta, which quickly became the No. 1 app on the App Store, maintaining a high ranking for weeks and amassing millions of downloads. Over a month later, Delta remains popular, currently holding the No. 33 spot overall on the U.S. App Store, while another emulator, PPSSPP, now occupies the No. 5 position.
However, the increased visibility brought its own challenges. Unlike the more obscure GBA4iOS, Delta’s rise to prominence attracted attention from Adobe. According to a post on Mastodon, Adobe threatened legal action over Delta’s logo, alleging it resembled Adobe’s own.
“Adobe is threatening legal action because they think our logos are too similar — so we changed it,” the post read. “This new icon is an inspired design by Caroline Moore (@carolinemoore@threads.net), we hope y’all love it as much as we do.”
The original Delta logo featured a broken triangle similar to the Greek letter delta, while Adobe’s logo is a red and white “A” with a thicker design extending to the edge of the icon. Despite operating in different sectors—Adobe provides creative tools while Delta focuses on retro gaming—Adobe claimed the similarity could cause confusion.
Delta received an email from Adobe’s lawyer on Wednesday, May 7, requesting a change to avoid infringing on Adobe’s trademark. Adobe gave Delta until May 17 to respond but also contacted Apple to request the app’s removal for trademark infringement. Delta responded to both Adobe and Apple, explaining that its icon was based on the Greek letter delta, not an “A,” but agreed to change the logo nonetheless.
To preempt further legal issues, Delta introduced a new logo featuring a broken triangle. However, this redesign has not been as well-received, with some users suggesting alternative designs like using a lowercase delta symbol or commissioning new custom artwork.
Testut mentioned that the current logo is temporary and plans to update it again when Delta 1.6 is released. “We’re planning to update the icon again to a ‘final’ version — also designed by Caroline — soon,” he said, adding that he is not too concerned about the brand impact in the meantime.
