After Apple loosened its App Store guidelines to permit game emulators, the retro game emulator Delta — an app 10 years in the making — hit the top of the App Store’s charts. But the increased attention also brought the threat of legal action, as Adobe targeted Delta for sporting a logo that looked too much like its own.

Delta’s game emulator was built by developer Riley Testut, who had begun his experiments in this space by figuring out how to load games onto graphing calculators, before turning to iOS. The app itself evolved from Testut’s older app, GBA4iOS, which leveraged a loophole to run emulated games on iOS without jailbreaking an iPhone. Consumer demand for such an app was high — millions of people used GBA4iOS was while it was available. But Apple eventually locked things down and put GBA4iOS out of business.

Now, as Apple faces regulatory pressure to open up its App Store to increased competition, the tech giant began permitting game emulators in April. That’s opened up a whole new market for developers who had not previously been able to take advantage of the massive distribution power the App Store brings. In short, Apple would rather host these apps itself than have to compete with alternative app stores where the apps it had once banned could find traction with consumers.

Testut took advantage of the opportunity to launch Delta to the public and it quickly became the number one app on the App Store, holding a top spot on Apple’s Charts for weeks and gaining millions of downloads. More than a month later, Delta is still ranking fairly high as the No. 33 app overall on the U.S. App Store. The No. 5 slot, meanwhile, is now held by yet another game emulator, PPSSPP (a PSP emulator).

However, becoming the top app on the App Store has its drawbacks. Though a more under-the-radar app like GBA4iOS may have been ignored, Delta’s ride to No. 1 has brought increased scrutiny.

According to a post on Mastodon, Adobe came after Delta, threatening legal action because it thought Delta’s logo resembled its own.

“Adobe is threatening legal action because they think our logos are too similar — so we changed it,” the post explained. “This new icon is an inspired design by Caroline Moore (@[email protected]), we hope y’all love it as much as we do,” it read.

Both logos had featured a broken triangle, similar to the Greek letter delta. Adobe’s logo, however, is red and white, and its “A” is thicker and stretches to the edge of the app icon. Delta’s logo is purple and white, smaller, and centered within the app icon. They’re also operating in different spaces, of course, as Adobe offers a suite of tools for creatives, not a way to play retro games. It’s hard to argue there would be much consumer confusion over which logo was which.

Delta told us it first received an email from Adobe’s lawyer on Wednesday, May 7th, telling the company that its app icon infringed on Adobe’s “A” log and requested that it be changed in order to not violate “Adobe’s rights or the law.”

Adobe gave Delta until May 17 to respond, but then it received a second email from Apple stating that Adobe asked Apple to take down the Delta app for infringing on its trademark. Delta replied to both companies to explain that its icon was a stylized Greek letter delta, not an “A,” but that it would update the logo anyway.

To avoid any potential legal issues, Delta launched a new logo that looks like a broken triangle. The redesign isn’t as simplified and clean as before, unfortunately, leading some users to suggest it could have gone a different route — like using the lowercase delta letter, for example, or having custom artwork created as the new brand.

Testut tells us the new app features a temporary logo on its icon, but he plans to update it once again when Delta 1.6 rolls out.

“…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.”