Depending on how many photos you have, I imagine the indexing and analysing needed for this will take some time. To prevent wiping out your battery it probably only works when the phone is locked and on the charger too (that's certainly the case with the face recognition).
Depending on how many photos you have, I imagine the indexing and analysing needed for this will take some time. To prevent wiping out your battery it probably only works when the phone is locked and on the charger too (that's certainly the case with the face recognition).