Applications used by the average mobile user still demand less resources than those a quad-core phone can provide. In fact, it's still common to see people satisfied with the same dual-core phone they bought some years ago. Can you advice for octa-core adoption at this moment in time? As always, we can only guess the initial boon for this new technology will be linked to the need of running software that requires octa-core resources (as it occurs with PC's and former smart-phone generations). A clear segment for the adoption of the octa-core sets right now are gamers and power users. Latest ones most-likely having data processing-software on their desktop PC's or hosted in the cloud already. Quad-core is still delivering sufficient performance at a lower price in 2014. Should we really upgrade?
Why is this even a question? The number of available octa-core smartphones is incredibly low, and most applications aren't going to take advantage of the extra power. There's no reason to buy an octa-core phone, but they're not even that much different in price compared to a quadcore or dual-core device. Gamers nor power users are going to notice much of a difference with the extra cores for the time being.