Cover your children's faces with stickers before you share a photo. Everything happens on your iPhone.
Can someone remove the sticker with AI? AI tools can paint an invented face over it, but not the real one. The pixels under a sticker are replaced in a brand-new image, and the app checks the saved file before you can save it.
Why is Take Photo greyed out? Your device has no camera available, or camera access is off in Settings → FaceAnonymizer.
Where is my photo uploaded? Nowhere. The app works offline and has no server.