These days, it takes about one day for Apple to review an app or update submitted to the iOS or Mac App Store. It doesn’t matter if it’s a new app or just a minor new version. It doesn’t matter whether it’s paid, free, uses in-app purchases, or subscriptions. It doesn’t matter if the developer is an small company or a multi-national corporation. It doesn’t matter what category of the App Store it’s listed in. It simply takes about one day for the vast majority of apps to be reviewed.
Has your app review taken more than one day? It happens, but it’s probably not a sign that the average review time is increasing. Maybe your app triggered an extended review, or perhaps something is causing some discussion internally. If you think there’s a problem, you can contact the App Store review team.