All shopping malls, supermarkets, fast food outlets and some markets require the app. Also cannot go JB makan? How to siam? Ta pau from hawker centre I guess.
i noticed there are loopholes to this.
e.g. when i drove to my neighborhood shopping mall, there was no safe entry requirement cos the guard/ambassador was only stationed at the main entrance. all other lift lobbies, staircases, emergency exits, side gates, etc, were not manned by the mall staff.
also you can show the singpass mobile safe entry module screenshot to indicate to the individual shop staff that you have checked in but they don't bother to verify whether you have actually checked in.