superchunk on 12 May 2014
Since you already use iOS, might as well stick with it. (I greatly prefer Android, NEXUS to be exact)
But I am in similar situation. I have Nexus4 and wife has Nexus5. I'm waiting for Nexus6. My phone works great and I'd rather have a bigger upgrade than just a one year transition.
You know its coming this year and so long as your current phone works, why not wait.
Also, your sister's phone is likely the Note. Those are 6" screens while Apple's iPhone6 will be closer to 5", like most phones on the market.
