My one cent:
Since I did this in an old project you need only two steps:
1. Connect to the wifi hotspot of the esp8266
2. Connect to IP address of the esp8266
After that you can receive and send data.
Also make sure to implement some sort of watchdog on connection especially for the IP part, because from time to time, the esp8266 will disconnect the IP.
Thank you for your response. But is it really about configuring ssid and password without connecting to esp8266 directly?
I am looking for exactly the configuration method as in the ESP Touch SmartConfig application