Will Samsung need to cut its Android ties sooner or later?

I've been wondering since the S4 announcement whether we'll be seeing Samsung cut its dies from Android in the future. The main thing that concerns me is their reliance upon Google introducing new developer APIs potentially restricting their ability to provide future innovations.

For example, with the S4 they announced new temperature and humidity sensors along with software to support these. I won't pass judgement on whether these are useful sensors to have however I think it brings up an interesting point around third party apps which as history would show us are the true innovators when it comes to using a devices new hardware features. By introducing these sensors they've fragmented themselves from other android handsets and if developers were to write apps which depend upon these sensors using Samsung only APIs then those apps are in turn fragmenting the Android ecosystem. This ecosystem of course also containing Samsungs's other phones.

Now I don't know enough about the Android ecosystem to fully understand the implications of this from a usability point of view. Could apps using Samsung specific APIs be published in the google play store? How will they behave on other devices and can developers reduce users frustration by preventing them from downloading on unsupported devices?

On the flip side of this, what if HTC bring out bespoke APIs? How does this bode for Samsung. I'd be interested to know how exactly this kind of deviation from stock android APIs is handled with regards to market places.