3. How long would you wait?
http://www.flickr.com/photos/oatsy40/6198212129
4. “85% of mobile users expect sites to load at least
as fast or faster than sites on their desktop”
Strangeloop Networks
5. “At the beginning of 2013 mobile (excluding tablet)
accounted for 26% of our traffic, and we ended the
year with it contributing 33%.”
Stuart McMillan, Schuh
6. “Historically, mobile baskets have always been
lower value than desktop but just before
Christmas the difference was only about 6%”
Stuart McMillan, Schuh
7. “We’ve remade the Internet in our image… obese.”
Jason Grigsby
http://www.flickr.com/photos/mrtopher/1414159786
8. Mobile Pages are Growing
Requests
Size (kB)
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http://mobile.httparchive.org/
9. We’re relying on ever faster phones and networks
http://www.flickr.com/photos/willposh/3825768273/
10. 4G isn’t going to bail us out
77.3M
mobile connections
2-3M 4G
connections
Estimated 20% of connections will be LTE by end of 2017
GSMA Intelligence + operators
15. Latency is still the big issue
“In 2012, the average worldwide RTT to
Google is still ~100ms, and ~50-60ms within
the US.”
“we are looking at 100-1000ms RTT range
on mobile”
Ilya Grigorik
http://www.igvita.com/2012/07/19/latency-the-new-web-performance-bottleneck/
16. It’s not just about speed
http://www.flickr.com/photos/fastjack/2943793818
17. 3G Radio Resource Control
Idle for 12s
IDLE
1-2s delay!
1s delay
CELL_DCH
CELL_FACH
Idle for 5s
Exact timings vary and depend on carrier NOT device
http://web.eecs.umich.edu/~fengqian/paper/3g_imc10.pdf
19. What are mobile sites made of?
HTML
Fonts
Images
CSS
Javascript
Other
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http://mobile.httparchive.org/
21. Images are the Bulk of Download
Requests
Size (kB)
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http://mobile.httparchive.org/
22. Time to bury bitmapped images?
http://www.flickr.com/photos/tonyjcase/7183556158
34. CSS size is creeping up
Requests
Size (kB)
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http://mobile.httparchive.org/
35. 25% More Javascript
Requests
Size (kB)
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http://mobile.httparchive.org/
36. Added 160kB to page
Increased bounce rate by 12% on mobile
https://speakerdeck.com/lara/design-for-performance
37. We’ve fallen in love with web fonts
http://www.flickr.com/photos/splorp/4951916342
39. 300% Larger in 12 Months!
Requests
Size (kB)
30
25
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http://mobile.httparchive.org/
50. Embrace Constraints… Set a budget
“Usable within 10 seconds on GPRS connection” - BBC News
“SpeedIndex under 1000” - Paul Irish, Google
Requests, page size etc. are easier to measure but may not
represent real world experience
http://www.flickr.com/photos/communityfriend/2342578485
51. For a faster mobile site:
Move less bytes
Prioritise what you move
Move them while no-one is looking
Distract the visitor!