It's been a good year for Apple (NASDAQ:AAPL), as far as U.S. market share is concerned. After years of reporting smartphone operating system market share less than Google's (NASDAQ:GOOG)(NASDAQ:GOOGL) Android, the company clawed its way back to No. 1 in the three months ended December 2014 on the strength of its successful iPhone 6 and iPhone 6 Plus iterations. During that period, Apple iOS's U.S. market share topped Android by the slimmest of margins -- according to Kantar Worldpanel -- by reporting 47.7% versus Android's 47.6%.

Worldwide, Google's Android continues to dominate by greatly outpacing Apple in developing markets, on the back of lower-cost models with razor-thin profit margins, but Apple is making headwinds with high-end Android switchers. Apple CEO Tim Cook noted during his conference call:

But I would also point out that we had the highest number of customers new to iPhone last quarter than in any prior launch. And also that the current iPhone line up experienced the highest Android switcher rate in any of the last three launches in the three previous years.

If the newest rumors are true, it appears Tim Cook is doubling down on converting users from other operating systems by offering a trade-in program for Android and BlackBerry users.

Phone (gift) cards
While it is important to note the details are unconfirmed, the broad outline focuses on extending the terms of Apple's existing trade-in program. In the existing program Apple offers an Apple Store gift card for previous editions of Apple's iPhone, now it appears they will extend this to owners of other handset vendors. The gift card can then be used to buy a new iPhone, naturally.

This builds upon Apple's strategy of lessening the friction for Android users to make the switch. Around the time of Apple's iPhone 6 and iPhone 6 Plus release, the company published a detailed article to support Android users looking to make the change to Apple. And that makes sense -- photos, email, and content are shockingly effective barriers to prevent users from switching operating systems.

Will Samsung respond in kind ... or can Samsung respond in kind?
In the U.S. markets the question is if high-end Android maker Samsung will respond in kind with a switching deal of its own for its Samsung Experience stores. And the answer could affect its existing store relationship with electronics retailer Best Buy as Samsung operates a store-within-a-store format. Best Buy already has a trade-in program for store credit cards, potentially making a Samsung Experience store trade-in program a competitor.

Of course, Best Buy and Samsung could further partner to accentuate Best Buy's trade-in program with both possibly benefiting from increased in-store traffic -- especially in the lead up to Samsung's new Galaxy S6 and Galaxy S6 Edge iterations. Those units go on sale next month, and the company could use a catalyst to revive its struggling fortunes of late.

Interestingly enough, it appears Apple's extended trade-in program is slated to pre-empt Samsung's April rollout. If Apple's able to make it easier and cheaper to switch to iOS, Android may find itself in second place in the U.S. permanently.