Message when I try to add the device. (I was able to load a simple HelloWorld app using the desktop Arduino IDE.
The device found is not compatible
An Raspberry Pi Pico has been detected but unfortunately this kind of board cannot be used on Arduino IoT Cloud.
Is there a timeline for support?
Hi and thanks for sharing this question.
As you have highlighted, Raspberry Pi Pico W is not currently supported by the Arduino IoT Cloud. It is a very interesting product and the integration in the cloud is very important for us, so it is in our roadmap and it will be soon integrated.
Unfortunately, we don't have a committed date for the integration, but we will definitely announce it when it is ready, so stay tuned for that.
How about you properly integrate Nano Connect first? I was never able to use it with cloud as it failed every time at the last stage of the adding process because of the driver you supplied. I paid for rather expensive board in good faith, but I cannot use it to the full potential.
Hi,
Nano Connect is fully supported by IoT Cloud.
If you are experiencing problems with it, I would strongly recommend you to go to the Cloud section of Arduino Help Center and ask for help.
Ok I'll bite.
Hi, Its February 2023 now, has any progress been made on supporting PicoW with the Arduino IOT Cloud?
If so can you send me a link of how to achieve this, I am busy trying to connect a pimoroni enviro sensor to my other sensor collections on the Arduino IOT.
Thanks
Hi!
Not there yet unfortunately.
We'll share more news as soon as we can.
Almost April and no news... just purchased a plan and then i see that it's still not compatible srly?
Whould you look at that, May and still waiting 
Can you give us any news about the compatibility with the pico and arduino iot cloud?
Almost August and still waiting.... This is getting ridiculous.
September, almost October.
Don't expect great response from Arduino. The fact is the PicoW can be connected to the Arduino IoT cloud. I've done it on several W's now and also on a standard Pico that I added an ESP32 wifi processor from Adafruit onto, its actually a Pimoroni board to give me more flash space 16MB vs 2MB.. Now here's the rub, Arduino sells an RP2040 NANO connect fully "certified" for Arduino IoT cloud. So right there we know the RP2040 can get online, and the wifi chip is dealers choice as far as I have been able to tell. Now I'm an oddball I'll admit it I program in pure C and C++ (NOT what Arduino calls C/C++). I use the standard language with the RP2040 SDK from RPI to implement everything from LCD's to network connectivity. This is a much harder path. There is a good book on the Pico dedicated to getting it on Wifi with using pure C programming I highly recommend it. No if you are an Arduino user chances are you are looking for the easy out where there's just a module you install or click and bam you dont have to do anything. I think that's what you are waiting for. If that's the case then just move to MicroPython. Its a beautifully simple language and does most of the hard work for you like Arduino's pseudo C/C++ libraries do. With Micropython you can pretty much follow the very poorly written guide on the Arduino website for the 2040Nano Connect to lead you down the path. You will almost certainly have to modify some of the files from the github repo mostly timeouts, and use the latest daily build of MP available for your PicoW. MP comes at a cost and that is usage of RAM. You'll be down to about 190K of RAM post MP install. From there is about optimizing the code given by Arduino and your own to achieve your goals. Like pure C - Arduino doesn't have that overhead of taking RAM resources away but Arduino's language is all you know..well..good luck on waiting. I managed to get a PicoW connected with a Pimoroni BME 688 sensor reporting its values for all settings every 3 seconds to the IoT cloud, the lame switch button to turn on the onboard LED. I have a fire sensor, light sensor ltr 559 and CPU temp and Lipo battery backup voltage being displayed. That pretty much tapped me out on resources. I started to implement a pure C version to connect and the lines of code were spiraling out of control, to me it was worth losing a bit of RAM to get simpler access. This of course is standard username/passworth authentication (no certs) and no API's used though I've managed to get a auth token so API usage should be possible but I haven't bothered. I bought one of the 2040 Nano Connect's thinking it would be "better" connection wise. Yeah no. No difference expect in the hardware. I also purchased and ESP32Nano which is supported they say, I had to go way off the reservation to get it online. Now that I've figured that out I have mostly moved to ESP32's, any brand using an S2 or S3 chip I've gotten my hands on I can get online, and with 16MB of storage and 8 MB of SPI flash available as heap, YES 8 MEGABYTES! The sky is the limit, I ran out of sensors to hook up to it while connected to the cloud lol and I was also running an 3.5" LCD! I personally like the unexpected maker S3 ESP32 boards but pick your poison. My worst project was the one where I bought a Adafruit ESP add on module and hooked it up to a Pimoroni Pico, it works but the wifi module comes with no SPIflash so its not capable of doing much at all even in C. Its an obsolete component I dont know why they keep selling it. So yes it can be done, not in any official capacity from Arduino. I was utterly amazed and shocked and the horribly wrong and missing documentation for both the Arduino2040NanoConnect and the ESP32Nano. Hot hot garbage. If you know how to program in C/++ like the real deal, you can get them online without Micropython. Heck, by now I'm sure people on github have done all the hardwork for you and you can just import a few .c and .h files and do your thing. Don't get too excited once you do get them online, the IoT interface is very plain, the widgets are dismal and basic. Yes it'll show you the numbers but man 0 points for making it look nice. I'm hoping it will mature in time. If not plenty of competitors out there or just run the whole thing local with node red and mosquitto using mqtt. Lots of ways to get there. Best of luck! I'm going to go check my nodes giving me real time temps all over the house, cause you know thats super important lol 
Apologies if I've missed this elsewhere, I'm finding it hard to focus in on the exact info.
I'm sure Earle Philhower's code is excellent, but is there 'official' support for the Pico W yet?