Posted for informational purposes only. Most people don't need to know this. The OP probably does tough. :)
mc12345678:
Suggest using a tool such as google analytics
Agreed.
mc12345678:
or one of the other SE tools that provide similar data.
I'd agree with this too, if you didn't specify 'SE' <g>
mc12345678:
Otherwise more than likely have to comb the access logs.
This one I can't agree to - and here's why..... The type of device being used, or the screen size/resolution of the device can't be determined by the Server because this information simply isn't sent to the server, therefore, there isn't going to be anything in the access logs to find.
It is possible that the 'User-Agent' header may provide a clue as to the device, and in some cases they'll even provide the make and module of the device, but these headers are browser dependent (rather than device dependent), and they are easily manipulated by the end user, which makes this form of device detection very unreliable at best.
This is also why 'responsive templates' don't (generally) utilise the User-Agent field to 'do their thing', and rely on .css instead.
The Google Analytics (and similar tools), and modern responsive template designs overcome this problem by doing their stuff client side rather then server side. The clients' (the customers computer browser) creates and has access to a "Document Object Model" (aka DOM), which contains the info needed and a whole lot more.
Simple explanations about DOM can be found here:
http://www.w3.org/TR/DOM-Level-2-Core/introduction.html
https://css-tricks.com/dom/
This important thing for the OP to know is that the information needed is only available to the client itself, so to record this data there needs to be a method for the client to send this information back to the server or on to another server (eg: Google) where it can be stored, sorted and correlated. This is almost always done via an AJAX call, which in itself isn't too difficult to do, BUT if the OP wishes to store/correlate on their own server, they'd need to create the server code to handle the AJAX requests, and even more code to display the results somewhere/somehow. Again, this isn't too difficult, but since Google already have servers set up to handle all of this stuff, and a whole lot more, trying to replicate that 'in house' is a LOT of work, for little to no benefit, so in this basis, any of the Google Analytics modules is really the only practical way to achieve the aim.
Although I'm biased
https://www.zen-cart.com/downloads.php?do=file&id=1997 is probably the simplest/easiest of the available modules to install that will achieve the OP's requirements.
Cheers
RodG
NOTE: We are sorry that Rod is no longer with us.
We are grateful for all his contributions to the Zen Cart community.
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