To add another experience concerning out-of-date-iOS... I'm using an Ipod Touch 5, but still on ios7! But I'm sure my use case is different... I use an Ipod Classic for music. The IpT5 is relegated to a gaming device. With some other apps I use sparingly.
One big hit was about 1.3 years ago, Plants Vs. Zombies 2: It's About Time eventually required ios8 or later. I ended up playing on my iPad Air (1) instead which had ios8. I still play some games on there from time to time (after all, they're already paid for :\ ). I have another game, a card game, that won't seem to work on ios7, but does work on my ios8 ipad Air (despite the developer and game description saying it IS compatible with ios7).
I have 2 games that I had to stop playing due to glitches/bugs. Dunno if they ever got addressed, but I probably won't be able to get updates for them at this point.
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It's odd b/c when i first got my IpT3 around 2010, I got entrenched into iOS gaming all the way until the IpT6 was announced. that was the first time i did NOT get the next generation Ipod Touch, and my interest in iOS gaming waned from that point on.
