I know buying phones on telecom contract might not be most OzBargainers' preference. However with recent disappearance of cheap plans & $10 drop on this particular handset I think it might be a good price, especially for those who do not want to fork out a large sum for the handset upfront.
Sony Xperia Z 4G (Sony's top of the range phone around this time last year) — 1.5GHz quad core, 16GB storage, microSD slot, 5" full HD display, 4G LTE, locked to Vodafone.
$0 handset repayment on Vodafone's $30/month plan that gives you $200 call/SMS credit + 200MB data. Total minimum cost = $720. They are also running an online promotion at the moment with 2 months free access fees on new connections. So that's 26 months for $720.
Vodafone is getting better especially with their 4G.
Edit: and don't forget about the cashback!