How To Hide or Show HTML using isMobileRequest?

The Conditional expression has the following syntax which works on a Boolean Logic:

<b:if cond='data:blog.isMobileRequest == "true"'>

HTML To Show Only in Mobile Devices

</b:if>

The content inside the conditional expression above will load only in Mobile devices where the condition has value true due to the parameter ?m=1 where 1 means True.

If in case you wish to display content only on desktop devices then you will reverse the logic in this order:

<b:if cond='data:blog.isMobileRequest == "false"'>

HTML To Show Only in Desktop Devices

</b:if>

As simple as that. Note that this condition works irrespective of whether or not you have enabled or disabled the default Blogger Mobile template. You can use it in both cases.