Mine was 1kg at week 25. Gynae said he is a little on the bigger side but nothing much to worry about yet.
It also depends on the parents though. So if both you and your husband are taller/bigger, maybe that’s why your doctor didn’t flag it out.
don’t follow the app it’s just a guideline. if your gynae never flag anything then don’t worry. cos your gynae will take your medical history and health into account, but this app is just generic info