I'm on the straight number and upgrade every 2 years on th iPhone and am on the opposite cycle with my iPad so usually each fall I'm ready for one new device. I just got my 6 plus in 2014 and so t be ready until 2016.
I'm on schedule for a new iPad this fall but as I am now using my iPhone 6 plus 90% of the time. Unless there is something majorly new, I might not upgrade the iPad.
I like that, might do that with my phone and ipad.
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I was on the 4s and 5s cycle and loved it as it focused on improving lags or bugs and made some spec improvements for a better overall experience.
I couldn't help myself and went from 5s to 6 plus for the size. I don't do much in my phone but safari crashes a lot for me and tabs refresh apps get sluggish so the next s's will hopefully get that extra ram. I'm not used to my iPhone experience being hiccupy like this. I will jump back on s next round and remember this feeling as I'm sure the 7 will be yet another temptation but will come with many new "gates" the s will fix.
Yeah, one of the reasons I kind of wished I started with the S since I plan on upgrading every 2 years.