Apple has always emerged as a company known for its top notch quality. The processor and operating system i.e ios makes a lag free experience. The build quality of an iPhone is also adjudged better compared to sammys and other competitors. Also the app store contains each and every app required for your daily use.
I think most people would either choose Apple or Samsung. However, I don't really have that much experience with Apple products and in all honesty I don't really like them either. I have always stayed away from Apple due to the fact that once you're with Apple, you're stuck with Apple. They are also ridiculously expensive and that doesn't just go for their hardware, it applies to their software too. Personally, I am a fan of HTC - their HTC Desire is bulletproof! Seriously, it saved someone's life by taking a bullet for them when it was in their shirt pocket!
As always Apple brings in the best quality, but Apple iPhone for instance is not that cost-effective. To me Samsung offers a balance between good quality and affordable price. And whatever you choose, keep a good distance from "Made in China" tin toys, they are hardly worth the trinkets..!