The following question was taken from a post on a LinkedIn UX group I belong to. Below is my view with supporting research:
‘Are UX people concerned about how quickly web pages load on smartphones & tablets?’
Putting aside my usual ‘it depends on strategy, scope, budget, etc..’
For the mobile web, load time is an essential element of concern.Where broadband is available it is of less concern.
When you consider the skyrocketing growth of the usage of mobile devices, load time is critical for optimized user experience and conversion rates. About 1/3 of Americans use their mobile device(s) primarily to access the web. This number is only expected to grow globally.

Source: http://goo.gl/cGMYA
Currently mobile network connectivity can be spotty, which effects load performance. 74% of mobile visitors will abandon a site if they have to wait 5 seconds or longer for it to load. So we basically have 5 seconds to grab users attention; being light-weight for the mobile web not only holds tremendous competitive advantage, but also optimizes the UX.
There is also the whole RWD (responsive web design) vs. separate mobile website/app debate that should also be considered: it all depends…
Link to cited research (note you will have to enter an email to download full report and infographic): Survey Report: “What Users Want From Mobile” http://ow.ly/ggSOD
Link to Survey Report summary from Global News Wire: http://goo.gl/1y6n1
Written by Marc Niola – The UX Acrobat
Follow Marc on Twitter: @MarcNiola
About UX Acrobat - Marc Niola
Marc is an expert UX professional with a focus on customer-centered design principles, social media, gamification and psychology. He has developed innovative business solutions for global corporations, SME, agencies, clients and brands.
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