When i play around with Arduino’s which i have flashed and start with their own access points. It’s sometimes not clear which remote IP is connected.

Applications like Tasmota,Wled and Easyesp startup with their own Access Point, which you can use to connect to and configure them to your real accesspoint.
So you connect to this temporary AP, and want to remote access it with your phone’s browser. Not all apps (certainly not my apps) have a captive portal. Most won’t .. Which ip to use to connect?

Install JuiceSSH of you don’t have it .. it’s a must have really

Select quick connect – local device

Enter command “ip neigh”, It wil show devices connected to your android phone or which where broadcasting in your network-neighbourhood

Most of the times it also your default gw .. which can be found in settings. But above gives you more information.