Today I've received a new order from aliexpress.com.
A board with four relays working on 3V3.
I will use the relays to control the irrigation system that is now driven by a Raspberry Pi.
So, the ESP201 will replace the Raspberry Pi that did a very good job in the last three years.
I am using the 3V3 relays just for fun, I've tested the ESP201 with 5V relays and are working normally from my point of view.