I got my answer. Both iPhone 6 and 6+ and Google Nexus 6, when purchased unlocked (no carrier lock), and sim free (without a carrier sim) are full functional on any carrier. I pulled the two paragraphs below directly from reviews.
Google and Motorola only make one American-model Nexus 6, which covers every applicable band for AT&T, T-Mobile, Sprint, and Verizon. That includes 3G GSM and CDMA, as well as 4G LTE and carrier aggregation.
The contractless iPhone 6 starts at $650 and is compatible with Verizon (VZ, Tech30), AT&T (T, Tech30), T-Mobile (TMUS) or Sprint's (S) networks. The unlocked iPhone can also can be used abroad, letting people globe trot without being tied to a single carrier. It comes without a SIM card, which customers have to get from their cell phone company of choice.
The current carrier competition has me shopping for the best deal. However, I am only aware of the iPhone 6 and 6+ can be purchased as totally compatible with all networks in the USA and internationally.
I REALLY like my android. What other options do I have and best place to purchase?

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