I believe all of your questions can be answered/achieved by using IOTAppStory. 
 
I kinda wish Rui/Sara would do a tutorial for it.

1) As Steve Mercer said, the only solution that I know is using IOTAppStory to be honest I’ve never used it, but I recommend using this video to learn how it works:

• https://www.youtube.com/watch?v=_4NRqIa-cvo

ESP32 Over the Air only works on your local network…

2) With these examples the ESP should auto-restart after receiving the new firmware (no need to press the BOOT button)

I hope that helps!

Thanks for the answer,

I will treasure your advice,

I will study it.

Friendliness.

I actually thought I would give it a try myself and found this is is in a state of fluctuation. It’s not actually working for me. I have asked a few questions and will see how far I get.

Working through issues with IOTAppStory now and will advise of how I get on. First issue fixed.

Second issue fixed. Onwards and upwards…

Great! I am now working on other problems in my project. Thanks Steve!

I can’t wait to try your IOTAppstory!

Final Issue fixed. I now have a project/app on IOTAppStory that will auto update my ESP32 when changes are uploaded. It’s actually kinda cool. You can either export a .bin file from Arduino IDE or use the .bin file in PlatformIO then upload that to IAS (IOTAppStory) and your board(s) will pick it up the next time they “Call Home”. If anyone needs any help please don’t hesitate to ask.
 
Maybe Rui/Sara will create a tutorial for it. If they would like to I am happy to help.

Great Steve !!! 
as soon as the tutorial is available I will gladly try!
Thank you!

Hi Steve, I need to update OTA python scripts to multiple remote ESP8266: do you know how I can arrange this?
Each of them will be connected to a local WiFi network and to smartphones in the same net.
Thanks for any hint!

I’m sorry, I don’t use Python nor ESP8266 so no idea on these.
 
see if you can get remote OTA working with IOTAppStore. It should work. Just read the wiki and the YouTube video linked above.

Thanks Steve, I just dropped an email to them.

I would like to add my two cents in here. I did Rui’s esp32 course a year ago and was really pleased with his section on OTA with the esp32. I had been struggling with the 8266 with terrible results. The esp32 system using the compiled binary updates worked like a dream. But over the past several months things have quite working. Thinking I may have a faulty device, (at the top of a 40ft flagpole), I decided to set up up a new one before I tackled the replacement. I soon found that not one of the five devices I had worked correctly with the same code. Not only that I have encountered an issue where the device works fine as long as the usb cable is connected but then will not function with the external power. The one on the flag pole still works with the current code and turns on and off daily with a nodered timer and sonoff switch. But I am unable to communicate with it via wifi. Several of these unit I have on the bench work fine on wifi if the usb is connected. But will not work when the external power is applied. There are several others on the Arduino forum with similar issues. I just wonder if there was some library change that has been made causing this issue. I am still trying to navigate the IOTappStory to see if I can find a solution there.
Kentm

I have found that IOTAppStory only works with boards that have the standard ESP32 Core from Espressif. Other boards have modified this core for themselves. For example I have a Heltec WiFi 32 Kit board that works great. I also have an Arducam IOTAI that has a modified core to work with their own SPI cameras. This board is not supported (The IAS developers are working to add it).
 
If you need any help with IOTAppStory (IAS) let me know.
 
As for power issues. What power supply voltage and current are you connecting and to what pins? The USB cable is delivering 5V/500mA. Some of my boards do not like 3.3V and refuse to start WiFi with that. I believe the current draw is too high at that low voltage (I have not confirmed that yet) and my power supply can’t deliver. If I connect 5V to the FTDI pins it works great.

Steve,  Right now I have a mixture of boards all using the WROOM device and one has the Espressif device. That board is called a Mini32 about the size a wemos d1 mini. It came from folks at Acrobotic earlier this year and I haven’t tried it yet. As for power. these boards run fine connected to the computer via usb but don’t run with an external supply. My bench supply is good for 30v@10amps. The power supply for the flag pole is a 5v10a unit. I don’t believe power is the problem here. I have a current sensor in the negative lead of my bench supply that I hook to my scope and I can see no fluctuation when I apply the bench power. In the image that I enclosed you can see the variety of units. I did not send this image for evaluation, just to show the variety that all do the same.  The strange one is the pair of white ones label NodeMCU ESP-32S. The two pins in the lower right corner normally associated with 5V and GND are different. What is marked as ground on most chips is called CMD . Without a magnifier it easily can look like GND. I am going to reassess those two chips and also try the mini. It still has me concerned that this all reared it’s ugly head within the past couple of months and devices that used to work don’t any more. In the photo the chips on the left say ESP32 DEVKITV1, then the mini32, then the NodeMCU ESP-32S and finally on the right a wemos lolin32 v1.0.0.  I still have to test the mini. I will post when able
https://imgur.com/8yYzhpD
KentM
 

You can check which boards are currently supported in IAS at https://iotappstory.com/hardware/ESP32/boards.
 
It seems strange that all boards have stopped working. Let’s move off power issues. I’m thinking that’s not the issue. What antenna are you using? Did you move or change your router or router settings?My Heltec board uses the onboard antenna and has to be within 10 feet of my router. My Arducam board has an external 6DBi antenna and has way better range (I have not tested how far). Note that electronic components do degrade over time. Whilst it may have worked when new you could have been in a marginal situation that now is showing as the hardware degrades.

I went to Espressif forum website and found a workaround from a poster regarding the same subject. I don’t think the problem is caused by the chip maker as much as I think it may be caused by the myriad of board assembly people. The answer that was supplied was to connect the power to the device with the usb cable. I loaded my basic OTA code to the device from the PC, then removed the cable from the PC and connected it to my phone charging hub. I also had to make a connection to the 5vdc line on the led string. Everything works, leds light up, I can change the sequence with the wifi OTA and that’s where I was a year ago before all this mess started. Hopefully someone from Espressif will take note of that in their forums. As for the board itself, I have a GND, IO12 and no other connection. I modified a micro usb cable by cutting the large end off, locating the power leads and connecting that together with the leads for the led strings. There is NO connection to the 5vdc pin on the board. I also found that the .bin file that I used (NodeMCU esp32S) worked for the boards no matter who assembled them. 
YMMV
KentM