Not really much of a gauntlet compared to some of the others in this forum, but I ran across
this lifecycle study and thought I would start this as kind of a survey. I don't see a 2015 study on their website so I'm going with the 2014 figures.
Flat panel television 7.4 years --> I have a Mitsubishi DLP projection set which is about eight years old. I don't use it that much but it's had several lamp replacements and a DVM chip replacement ($$$) during that time. I expect to replace it with a real flat panel in the next few years.
Digital camera 6.5 years --> I have a 10 year old Casio which still takes excellent photos (better than my phone) but probably needs a new battery.
DVD player or recorder 6 years / Blu ray player 5.8 years --> I have a Panasonic Blu ray player just over 2 years old. It replaced a 3 year old Sony which died and was replaced once under warranty. That replaced a ~7 year old Apex which died.
Desktop computer 5.9 years --> I have a 4+ year old iMac. Recently upgraded to a SSD, will easily exceed the 6 year mark before I replace. Will probably replace both the desktop and laptop with a laptop (possibly not a Mac) and dock it to a monitor/keyboard.
Video game console 5.7 years --> None. I do have a first-gen Chromecast.
Laptop computer 5.5 years --> I have a 4+ year old MacBook Air. Still very fast, battery still holds a good charge with 750+ discharge cycles. As above, will easily exceed the average. Will probably get replaced at the same time as the desktop with a single machine.
Tablet computer 5.1 years --> 3 year old iPad mini. It is very slow. Not sure I will be able to resist upgrading once the iPad Air 3 comes out. I used to dislike the full size iPad, but have warmed up now that they are thinner and lighter.
Non-smartphone 4.7 years --> Don't have one.
Smartphone 4.6 years --> 2 year old Nexus 4, which replaced a 3 year old iPhone 4, which replaced a 3 year old iPhone. Would like to go back to the iPhone because I think privacy is better on that platform, but I do like the form factor of the Nexus 5x. Battery life is poor, but the Nexus 4 is still very responsive and feels faster than the iPad mini, maybe it will last me longer than 3 years?