The NimBLE based host/server solution for BLE connectivity with ESP32 defined as a server in ESP IDF environment The code: Android phone BLE software: Nordic Semiconductor - nRF Connect For version the "esp_nimble_hci_and_controller_init" have to be updated to "esp_nimble_hci_init" - thanks to @user-dl5ls8bi5o and @stefanwunder4767