It's rather a large assumption that all activities are available all the time.
Originally Posted by supergtdman
For those of you reading this post, are there times when you have a strong broadband connection on your computer, but not on a mobile device that uses cellular technology? In that case, your @Phone context may not be available, but your @Online context is. Are there times when you could work more efficiently on a larger screen, rather than trying to surf on a smartphone or tablet? In that case, your @Online context may be available, but only on a mobile device. Home broadband is widely available, but for many people it still has slow times and outages.
I've been in Los Angeles and the Bay Area recently, both densely populated economic hubs. In both I have had to cope with low to no cell coverage, and sometimes unreliable wired broadband access to the internet. Flexible contexts turned hours of offline time into productive time.
Refining my contexts to improve my efficiency is what makes them valuable.