Hi, i have 6 years of embedded and iot system development experience. project experience includes medical, access control, attendance, beacons, ble, GPS , electronic fluid dispenser etc.
i am experienced in ESP32 too, working on it since past 2 years. i see lot of peoples using APN server approach to configure ESP but you can see BLE too. i had shifted lots of my client to this approach and it work seamlessly. although I can help you in both approach but I would suggest to use BLE for your Anroid/iOS app. i will develope flutter app for both this will reduce time and efforts. since same code base will be used by both.
please consider me for your requirement and lets have a chat to discuss in details