user7951: I have an Arduino Uno and I have a remote sensing project for which I need Wifi connectivity. After doing research, I've found that I have 2 options:

Buy a WiFi shield for my existing Uno
Buy an Arduino Yun with built-in WiFi

Looking at costs, I found that a WiFi shield costs more than double what it costs to buy a Yun, so it would seem to me that the best option is the Yun as I'd save some cash and get a more capable board. However, I can't help but think I'm missing something. 
What are the advantages of an Uno plus Wifi shield as opposed to a Yun?

user18478: First of all yun is not the same as uno + wifi shield. yun is more like a linux pcc with wifi and a lenoardo.
If you are asking for your options there are more options. For what you want I would go for a ESP8266. Again there are 2 options here:  

uno + ESP8266 (as a wifi shield)
ESP8266 (as a dev board)

I think it is pretty obvious that the ESP8266 (as a dev board) is the most cost effective.
You can program the ESP8266 just like a uno in the arduino IDE.
So I would advice to take that board.

user4143: There's a number of things to consider that could sway your choice one way or another:
Power consumption
The Uno is a small low-power chip to which you add WiFi. The Yun is an Arduino Leonardo with a WiFi router (like you have on your desk) strapped to the back of it.  The Yun will therefore consume considerably more power than the Uno.
Boot time
The Uno takes about 1 second to boot up - faster (instant) if you remove the bootloader and program it direct with a programmer.  The Yun takes minutes to boot.
Stability
The Uno is a solid state single item. The Yun has an entire operating system with filesystems and things.  It's far more likely that the Yun will corrupt itself through power loss than an Uno will get struck by a stray neutrino.
Cost
Yes, the Yun is cheaper. But is cheap always good?
Remote-ability
The Yun can be completely reprogrammed remotely. A new sketch can be uploaded to the Leonardo portion of it without you even having to be in the same country. The same can't be said for the Uno.
Power
The Linux portion of the Yun is considerably more powerful than any normal Arduino. 

7951: <p>I have an Arduino Uno and I have a remote sensing project for which I need Wifi connectivity. After doing research, I've found that I have 2 options:</p>

<ol>
<li>Buy a WiFi shield for my existing Uno</li>
<li>Buy an Arduino Yun with built-in WiFi</li>
</ol>

<p>Looking at costs, I found that a WiFi shield costs more than double what it costs to buy a Yun, so it would seem to me that the best option is the Yun as I'd save some cash and get a more capable board. However, I can't help but think I'm missing something. </p>

<p>What are the advantages of an Uno plus Wifi shield as opposed to a Yun?</p>
 18478: <p>First of all yun is not the same as uno + wifi shield. yun is more like a linux pcc with wifi and a lenoardo.<br>
If you are asking for your options there are more options. For what you want I would go for a ESP8266. Again there are 2 options here:  </p>

<ul>
<li>uno + ESP8266 (as a wifi shield)</li>
<li>ESP8266 (as a dev board)</li>
</ul>

<p>I think it is pretty obvious that the ESP8266 (as a dev board) is the most cost effective.<br>
You can program the ESP8266 just like a uno in the arduino IDE.<br>
So I would advice to take that board.</p>
 4143: <p>There's a number of things to consider that could sway your choice one way or another:</p>

<h1>Power consumption</h1>

<p>The Uno is a small low-power chip to which you add WiFi. The Yun is an Arduino Leonardo with a WiFi router (like you have on your desk) strapped to the back of it.  The Yun will therefore consume considerably more power than the Uno.</p>

<h1>Boot time</h1>

<p>The Uno takes about 1 second to boot up - faster (instant) if you remove the bootloader and program it direct with a programmer.  The Yun takes minutes to boot.</p>

<h1>Stability</h1>

<p>The Uno is a solid state single item. The Yun has an entire operating system with filesystems and things.  It's far more likely that the Yun will corrupt itself through power loss than an Uno will get struck by a stray neutrino.</p>

<h1>Cost</h1>

<p>Yes, the Yun is cheaper. But is cheap always good?</p>

<h1>Remote-ability</h1>

<p>The Yun can be completely reprogrammed remotely. A new sketch can be uploaded to the Leonardo portion of it without you even having to be in the same country. The same can't be said for the Uno.</p>

<h1>Power</h1>

<p>The Linux portion of the Yun is considerably more powerful than any normal Arduino. </p>
