A great flagship phone should easily last you three to four years. Instead of jumping on pre-orders the second a new device drops, the smartest move is to wait for the launch event itself. That is when last year's top-tier model instantly drops in price, or when the new version is actually available for real-world testing.
If you want to bypass carrier contracts and buy your phone unlocked, you will need to cover about $900 upfront. We can stretch that cost out over more than a year without paying extra fees or interest by using the right card.
Keep in mind that the 15-month intro window is a strict deadline, not free money. If you still have a balance left when the promotional period ends, the regular variable interest rate will kick in on whatever is left, making your upgrade much more expensive.