Don and others:
In spite of probably being one of the last technology-impaired collectors in the US of A (no smart phone but two laptops), I understand Don's vision to move much of the web presence to mobile devices. But I would not want to see this move made at the expense of the vast library of PDF based books, journals, and other resources currently available on the internet. The two media formats should have some common grounds for co-existence.
For immediate information, mobile devices and appropriate Apps or web pages are desirable. But for serious, extensive reading, I'll go with my Laptop (Who among you wants to read
War and Peace on his smartphone?). For long term knowledge and large publications, I see nothing wrong with having these philatelic publications available in PDF format - which is available to virtually anyone with the sense to turn on a computer, or additionally in one of the current ePub formats. The advantage of PDF is that it has been around a long time, is robust, and everyone knows how to use it.
AND, even more important, should the researcher actually download the publication's PDF file to his computer, he will have it forever, or at least until his un-backed up disk crashes, and will not be at the whim of some website manager. How many of you can't find a title on Google Books that you found last year?
While I might visit the APS or another philatelic website for a quick search for information, for long term research references, I'll stay with my PDF files.
What I believe is currently needed, is what I think
hoosierboy was trying to suggest in an earlier post, is that there should be some common central vehicle to bring together
all of the available information about the internet locations for all philatelic resources and postal history resources
under some form of a common umbrella. The Collectors Club of Chicago has a number of their published books available for free downloading at their site. The US Classics site has another group of useful publications. The StampSmarter web site has more. But there is no one single location where can one go today and learn about all of these -- and the vast multitude of materials in Google Books and other digital libraries.
I made an effort several years ago to document the internet locations of many of the official publications of the US Post Office Department and US Postal Service. My approach was to create a group of PDF files, with one for each major USPOD series. e.g.:
The Official Postal Guide, Reports of the Postmaster General, etc., with the name of the publication, it's year of publication, and one or more URL links to that publication. I stored a version of these files on the
Texas Postal History Society website at
http://www.texascovers.org/featured-articles/Anyone can download these files to their computer. All that is needed is to open the file locally (I keep mine in a folder on my desktop), find the particular volume of interest, and select that URL. BINGO !, I'm there.

I've done these for other groups of digital books related to my other research interests, but at the present they are not generally available.
Another possible solution, one that might be more viable in the long run, is for the American Philatelic Research Library (APRL), or their Union Catalog Consortium, to create links to these digital on-line publications, as part of their entry for that publication in their catalog record. The APRL has already begun to include some references to digital publications (there is a selection box on their Advanced Search page to retrieve only digital publications), and its should be much easier to add the appropriate entry in these Union Catalog entries than create an entry on some webpage somewhere. Besides, most knowledgeable researchers will check the Union Catalog first or second anyway.
I appreciate that such effort will cost some someone some resources, so I offer it only as a suggestion. But I suspect that there are many readers who would gladly provide the APRL with a list of Titles and their internet location URL for publications they have found in their searching, and would like to see them included in the Union Catalog.
Constructive discussion welcomed !

Mike