Face2FaceAI copies a facial expression from one photo (the Source) onto a face from another photo (the Target), then places the edited face (the Result) back into its original photo. You move left to right in the app through three bottom tabs: Input → Blend → Output. All processing happens on your device — photos never leave your phone. Tip: first time through, long-press any control for an instant explanation, or look up controls by name at any time in the Help Glossary in Settings.
The three previews show your Source Face, Target Face, and Result Face. Set the sliders, then tap Run Blend (a few seconds to process). Before you run a blend with non-zero settings, Result Face just shows a copy of Target Face.
Re-run as often as you like, adjusting in small steps for best results. For additional suggestions about possible fixes, check out Troubleshooting, also in Settings.
Using a Template as your Source. Instead of a gallery photo, tap the Source upload button → Expression Templates for a built-in library of expressions across five characters. For the closest match, pick the character whose face most resembles your Target. If one character’s version doesn’t blend well, try the same expression on a different character (“By Expression Name” in the menu). Templates often show a long neck — if your Target doesn’t, switch the Source to Manual Location Mode and move its BBox up so the neck is hidden; this noticeably improves results.
Fixing an asymmetric selfie (one face). Load your selfie as the Target. Then load the same selfie as the Source and turn on Mirror in the Source panel — the mirrored copy balances the two sides of the face. In Tab 2, run the blend with intermediate settings (around 0.5) for Eye Expression, Other Features, and Head Position, and Finalize with Reinsertion. If the eyes end up looking the wrong way, set Eye Expression to 0.0. If the corrected face looks stiff or blank, lower all sliders until it looks natural again — even a gentle correction visibly reduces asymmetry.