Following Apple’s relaxation of its App Store guidelines to allow game emulators, the retro game emulator Delta—an app a decade in the making—soared to the top of the App Store charts. However, this newfound visibility also brought legal threats, with Adobe targeting Delta over a logo that bore a striking resemblance to its own.
Developed by Riley Testut, Delta’s journey began with experiments on loading games onto graphing calculators before turning to iOS. The app evolved from Testut’s older creation, GBA4iOS, which used a loophole to run emulated games on iOS without needing to jailbreak the iPhone. The demand was high; millions used GBA4iOS while it was available. However, Apple eventually closed the loophole, shutting down GBA4iOS.
With Apple now under regulatory pressure to open up the App Store to more competition, the tech giant started allowing game emulators in April. This change opened a new market for developers who previously couldn’t benefit from the App Store’s vast reach. Apple preferred to host these apps rather than compete with alternative app stores which might attract consumers.
Testut seized this chance to launch Delta to the public, catapulting it to the No. 1 spot on the App Store and holding that position for weeks with millions of downloads. More than a month later, Delta still ranks high as the No. 33 app overall on the U.S. App Store. Another game emulator, PPSSPP, now holds the No. 5 position.
However, Delta’s rise to the top brought increased scrutiny. According to a post on Mastodon, Adobe threatened legal action against Delta, claiming its logo was too similar to Adobe’s. Delta explained, “Adobe is threatening legal action because they think our logos are too similar—so we changed it.” Caroline Moore designed the new logo.
Both logos featured a broken triangle, resembling the Greek letter delta. Adobe’s logo is red and white, with a thick “A” stretching to the icon’s edges. Delta’s logo is purple and white, smaller, and centered. The two companies operate in different industries, making consumer confusion unlikely—Adobe provides creative tools, while Delta is a retro game emulator.
Delta received an email from Adobe’s lawyer on May 7, stating that the app’s icon infringed Adobe’s “A” logo. Adobe requested a change to avoid violating Adobe’s rights. Adobe set a response deadline of May 17, but soon after, Delta got an email from Apple, noting that Adobe had asked for Delta’s removal for trademark infringement. Delta replied to both companies, explaining its logo was a stylized Greek letter delta, not an “A,” but agreed to update it.
To prevent further legal trouble, Delta introduced a new logo that appears as a broken triangle. While some users preferred a different approach, such as using the lowercase delta letter or custom artwork, the redesign was necessary.
Testut mentioned that the app currently features a temporary logo, but he plans another update with the release of Delta 1.6. “…We’re planning to update the icon again to a ‘final’ version—also designed by Caroline—soon,” he said, adding, “we’re not too worried about brand impact in the interim.”
