I think Apple at this point does not have anything to worry about. The S4 and HTC one are coming out, but really all Apple has to worry about is the S4. The HTC One is nothing special, and will not really cut into the sales of the iphone or S4. Sure the One looks really good, but with just a ok camera, weak battery, and sense 5 looking like a mess I don't think Apple or Samsung have anything to worry about. The iphone 5s will sell like crazy because it Apple next iPhone, and the S4 will most likely be even or popular then the S3. I think we are coming to the day were samsung is the only android phone that is going to battle with Apple in the smartphone market. Sure HTC can keep releasing phone, but they are never really going to sell like iphones will.
With all that said I don't think either the S4 or One can come any were close to my Note 2. The battery will out last both of those without question. The note 2 is just as fast and both, and the camera looks great. Until the note 3 comes out android phone on the market will be any better.