ContactOne does the slow part — looking at every contact and figuring out which ones are the same person — so you only ever see the decisions that matter.
One iOS permission prompt. ContactOne reads your local contacts directly — no upload, no signup, no account. You can try a sample dataset first if you'd rather peek.
ContactOne shows you side-by-side what it thinks belongs together. You pick the photo, the name, the right number. The rest is auto-merged from what's already consistent.
Merges write through to iCloud / Google / Exchange like any other contact edit. Anything you regret, the History tab can reverse with one tap.
