Fashioned on the Dashboard "Email Addresses By Domain" feature, having the ability to have aggregated data on the devices opening emails would be beneficial, especially when considering pre-header text for emails.
Love your suggestion.
I am aware that there are solutions out there that will report on devices opening emails. Every platform that offers this type of reporting purchases their data from one of a handful of data aggregators who specialize in what is called "user-agent" data. (At one of my previous companies, we used DeviceAtlas as our data provider). These are basically massive data files containing virtually every imaginable user-agent string (which is always collected at time of email open). For each user agent, these data files include attributes which are used for reporting.
The drawback is that these files are very expensive and they have to be continually refreshed. Of course, this cost is typically passed on to the consumer. I've held off on implementing this same reporting capability in Maropost because (a) I don't want to raise the price to our clients, and (b) the data is still too expensive to absorb the cost wholly or in part. If using this data becomes more economically feasible then absolutely this is something that I would put into our platform.
Vice President - Product Development
Maropost Marketing Cloud