English please. Most people here do not understand spanish. I google translated your message and I would like to ask you something. When you say Arduino you mean a physical Arduino or an Arduino project possible for an ESP8266. If it is the second you can use MQTT. But if it is the first you can use the serial in B4R just by loging (f.e. Log("This is my Data: ", iMyData, " and this is my second data: ", iMySecondData)
. Then in B4A side you would have to use a library which takes advantage of the USB (I know it exists but since I 've never needed anything like that I cannot get you there) - just search the forum or alternatively you can go to google and search for "site:b4x.com b4a library USB of phone".