iOS 27.2 starts marking AI-made images on the iPhone with SynthID. Pictures from Image Playground and some AI edits in the Photos app now carry an invisible watermark that says generative tools were involved.
Apple’s iOS 27.2 release notes describe it as SynthID watermarking to help identify whether an image was generated with generative tools. Apple said at its September event that SynthID support would arrive in a software update later this year, and this is that update.
Image Playground images and large Photos edits get the watermark
The watermark applies to everything you create in Image Playground. In the Photos app it applies to the edits that change the most, which are Extend, Reframe and large edits made with the Clean Up tool.
A small Clean Up edit that removes a stray object does not necessarily carry it. That matches what Apple said in September, when it described SynthID as baked into most edited images, depending on what was done to the photo.
The watermark is invisible, so an edited image looks the same to you as it did before. Only a detector can tell the difference.
Anyone can check an image with Google’s SynthID Detector
The check happens outside the iPhone, on Google’s SynthID Detector at synthid.com, which Google opened to everyone in October. Upload an image there to see whether it carries the mark.
That makes the watermark useful to people who never touch the Photos app. A reporter, a marketplace seller or a friend you sent an edited picture to can check the file without any Apple software.
SynthID and Apple Reference Image answer different questions
Apple now has two separate tools for image trust. Apple Reference Image on the iPhone 18 Pro and iPhone 18 Pro Max proves a photo came straight from the camera sensor. SynthID flags images that generative tools created or changed.
Reference Image is opt-in and limited to the iPhone 18 Pro models. A sensor in the Main camera signs the image data at capture, and Private Cloud Compute turns it into what Apple calls an unalterable reference image. It is not available at launch in China, and the capture side is not available in the EU.
A photo shot in Reference mode has a signed original, and a large AI edit carries a watermark. A picture with neither gives you less to go on, and that is the gap both features are meant to narrow.
Apple is not the only company marking AI output, and Anthropic will watermark Claude output worldwide as well.
