Right. But it still seems to be an overall increase of 20-30% for lightest of the use cases.

>In general you’re looking at a 20 - 30% increase in memory footprint when dealing with an all 64-bit environment. At worst, the device’s total memory usage never exceeded 60% of what ships with the platform but these are admittedly fairly light use cases. With more apps open, including some doing work in the background, I do see relatively aggressive eviction of apps from memory. The most visible case is when Safari tabs have to be reloaded upon switching to them. Applications being evicted from memory don’t tend to be a huge problem since the A7 can reload them quickly.

I've always expected they would start to serialize open tabs to the flash storage to keep from having to reload them from the network. Seems (to me) like that'd be easy to do.

Yes it would be easy, but the flash in these devices is quite slow compared to an SSD. Also what is the impact on energy usage?

Could you point me to a URL that shows that iOS7 have compressed memory? I couldn't find an official mention of it (maybe I'm searching for it wrong).

There's no official mention, but a few jailbreak developers have specifically talking about its existence. (MuscleNerd and Steffan Esser if my memory serves)

I guess it's mavericks not iOS7.