The cost of a smartphone can vary wildly - anywhere from $50 (or even less) to over $1000 depending on just which phone you're talking about. That wide range of prices also means a wide variety of devices are out there that cater to the specific needs or desires of you, the consumer. There are also a growing number of ways to pay for your phone if you really want the expensive stuff.
In America, phone subsidies from carriers (mobile operators) were long the preferred method to acquire a phone. In exchange for a promise to stay with a carrier as a post-paid customer for two years or more, the carrier would greatly subsidize the cost of a smartphone up front. So, instead of paying $650 for a shiny new iPhone, you could pay $200 to AT&T (or $300 for the 32GB, $400 for 64GB) and then "upgrade" (renew your contract) after 24 months of service to a new device. You also sometimes got "early" upgrades for iPhones allowing you to re-up your contract a few months ahead of schedule, because AT&T believed that holding onto the customer was worth taking a hit on the devices.
Things have very much changed in the last few years. Now, most post-paid customers are paying full-price for their devices - they just may not think of it that way - via financing or [regrettably] phone leasing arrangements. So, instead of $200 up front, you pay $30 a month for that iPhone and are free to leave AT&T at any time you want - though the remaining balance becomes due the moment you do. This practice has proven lucrative for carriers, because while it does mean a bit more management and working with a creditor (and therefore, debtors), they're no longer actively subsidizing these rather expensive smartphones.
That leads to this week's question: how much did you (or will you, eventually) pay for your smartphone? Was it subsidized? Are you on a phone lease (note that a lease is different from financing because you only have an option to buy the device at the end of a lease)?
For those on financing plans, answer based on the total you will eventually pay once all your monthly payments are complete. For those who are subsidized or on a lease program, note that there are separate options for these situations. For non-US readers, convert the cost in your local currency to US dollars.