Mobile bandwidth is somewhat of a red herring. While ubiquitous 4G isn't reality, most smartphones and networks are already capable of fairly high bandwidth.
Latency is the bottleneck you should tackle first when addressing mobile performance, not asset size - the world has already spent a lot of time optimizing asset size for web delivery. But phones are bad at handling lots of requests. Serving a single high-resolution graphic will have significantly less impact on page rendering speed (and even more important, perceived rendering speed) than a handful of smaller assets which add up to the same size.
For a real world example, a mobile phone can download and render a single large photo faster than the gaggle of javascript, css, and social network share icons typically presented next to it.
Agreed it's an issue - considered including it but didn't.
It's fair to question how much developers should concern themselves with external costs for using their service.
Do we have a responsibility to design for data caps to prevent unnecessary charges? Do we have a responsibility to do the opposite, as an industry exerting pressure on carriers to increase cap levels? Somewhere in between?
Honestly, I don't know. I'm inclined to design for a user's reality rather than a principle, but that "in the real world" thinking allowed the web to be dominated by "best viewed in IE6" sites.
> It's fair to question how much developers should concern themselves with external costs for using their service.
I wouldn't go so far as to say we have a solemn duty to always take such issues into account. But as a designer/developer, it is certainly something I myself would spare a thought for because - putting on my consumer hat - I am directly affected by the problem of shitty data plans at present and I'd like to think it's something that designers/developers would be aware of, regardless of whether they then make an informed choice one way or the other.
> Do we have a responsibility to do the opposite, as an industry exerting pressure on carriers to increase cap levels?
I'd like to think this would work. But I really just can't see it.
I too would be leaning towards designing for ther reality. But it seems we're in the time of 'case by case basis' on this issue. I don't think there's a single correct answer.
Latency is the bottleneck you should tackle first when addressing mobile performance, not asset size - the world has already spent a lot of time optimizing asset size for web delivery. But phones are bad at handling lots of requests. Serving a single high-resolution graphic will have significantly less impact on page rendering speed (and even more important, perceived rendering speed) than a handful of smaller assets which add up to the same size.
For a real world example, a mobile phone can download and render a single large photo faster than the gaggle of javascript, css, and social network share icons typically presented next to it.
Many have examined and written about this. Here's a blog article that Google ranks on the subject: http://www.webperformancetoday.com/2012/04/02/mobile-versus-...