The biggest thing with Arduinos specifically is that the cheap ones don't really have the capacity to negotiate proper web services. They can't handle HTTPS, yo

The biggest thing with Arduinos specifically is that the cheap ones don't really have the capacity to negotiate proper web services. They can't handle HTTPS, you are not going to be deserializing JSON in RAM, etc. By the time you pay for something like a Yun, you've spent more than a Pi. Also (prior to esp* WiFi breakouts) WiFi integration used up most of your I/O and cost 30+ dollars. I've been playing around with a couple of CHIPs[0] that are cheaper than most Arduinos and come with Bluetooth, WiFi and USB built in, a bunch of memory, and run ARM Debian. They use NAND for storage so you don't need a SD card for the OS, and the forums are pretty active for a pretty recent hardware platform. Other than still trying to get some SPI stuff integrated I've had no problem doing stuff I wouldn't want to use a Pi on and could not really use an Arduino on. I believe they're of better specs than anything but the latest Pi, maybe that as well. For $9, I've been very happy with it, but I can't compare it to the ESP as I have a few laying around and haven't used them yet. [0] https://getchip.com https://getchip.com