What phone do you recommend to upgrade to from a Nexus 5? Samsung Galaxy Note 5 or iPhone 6S Plus?

I have never owned an iPhone, but used an iPad Air before very briefly. I have also used a Samsung Galaxy S for a short time. The first smartphone I had ran Windows Mobile 6.5 (HTC HD2), The second was my first Android (EVO 4G LTE). The third is my current one (Nexus 5). IOS is very well-optimized since Apple makes both the hardware and software. However, Android is more flexible with customization. IOS devices get updates on day 1 regardless of the carrier. For Android updates, I will more than likely have to wait months to receive them on a Samsung Galaxy phone. My carrier is Sprint if that helps in any way. I plan to upgrade to a phone with a regular 24-month lease plan. List some other differences between the iPhone 6S Plus and the Galaxy Note 5. Explain why I would pick one over the other?

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