For this to become a fact, Apple's marketshare would have to take a SIGNIFICANT plunge given they currently own nearly 45% of the US market and a decent share of the European market.
Add in all high end Android devices and you're WELL OVER 50%.
I don't see iPhone users bailing on their beloved device just because some cheap Chinese knockoff comes along.
Could it affect high-end Android OEMs? Absolutely. But it's pretty obvious the high-end (price-wise) Android market doesn't make up a large percentage of Android's overall share (I think high end Samsung devices like the Note 4 and GS5 make up somewhere around 20% of their total devices sold - that's an estimate based on some pulled together data).
All-in-all, I don't expect companies like Xiaomi or Oppo to make much of a dent in the US or Europe.
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subsidies are not going anywhere here in Europe where they are the primary selling point for both consumers and carriers.
Contract length is increasing which suits carriers - and subsidies are increasing which suits the consumer who thinks they are getting a cheap phone.
And here in the US, the model is moving away from "subsidies" and toward calling them what they've always been - interest free financing built into your bill.
You can either pay $1000 for your 128GB 6+, or you can charge it, interest free and take on an extra $55/month to your cell phone bill.
Either way, the overall cost of the device is somewhat mitigated when the option of interest free financing is available. Best of all, I didn't have to pay anything up front.
I think people underestimate the brand loyalty Apple has and Samsung is building. They already make up a vast majority of smartphone sales anyhow here in the West. People are used to spending a certain amount of money for a specific product. They won't necessarily change just because its cheaper.
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You know, I am actually all for off-contract pricing. I would be quite happy if subsidies go the way of the dinosaurs. Without subsidies the smaller players selling inexpensive phones would certainly get more exposure; competition is good. Most people wouldn't be so quick to jump ship on that new S6 or iPhone 6S if they have to pay almost a grand up front.
I think you underestimate the brand loyalty these companies have.
And while traditional subsidies may go the way of the traditional 2-yr contract, there will still be interest free financing options with zero down (AT&T Next, T-Mobile JUMP etc).
I don't care how cheap the device is or what processor it has. I wouldn't replace my iPhone with any other brand.
And if I couldn't afford a new iPhone, I'd keep the one I have rather than upgrading to a cheaper Xiaomi or whatever. I can guarantee I'm not alone - likely in the majority of iOS/Apple users.