You can perform remote firmware updates using ESP8266.

Hardware Setup

Add Includes to Skecth

#include <ESP8266WiFi.h> 
#include <ArduinoOTA.h>  // Enable Remote Updates

The password is same API_KEY

#define ODEV_API_KEY "XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX"

The first upload must be done by the Serial, the others can be done by the network.

Upload ( Direct PUSH )

On serial console you can see the IP:

Only if module is connected to network, after a couple of seconds, the esp8266-ota port will show up in Arduino IDE.

If it does not appear in the list, restart the IDE.

selection of OTA port

If it still does not appear, you can use the option: Upload ( Manual PUSH )

On linux, you can scan

avahi-browse -rt _arduino._tcp

Upload ( Manual PUSH )

This option uses the command line (terminal) to upload.

Goto esp8266 tools folder (Ex.: /home/user/.arduino15/packages/esp8266/hardware/esp8266/2.X.X/tools)

Run command (change IP, APY_KET and FILE)

python espota.py -i IP.IP.IP.IP -a "XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX" -f /tmp/pathTo/Sketch.ino.bin

To find path to firmware you must enable verbose output in Arduino preferences:

Much information will appear, look for the file ending with ".ino.bin" on console

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