What are the best alternatives to an iPhone?

I'm now using an iPhone 3 and am due an upgrade in April. IPhones seem so expensive so I was wondering what I could replace this phone with. I like using the Internet, notes, camera, music, and I must be able to play pocket trains. Are there other phones that can do these things?

Samsung Note 3 or Galaxy S5. Note because you can use stylus to hand write stuff. Comes in handy when you solve math problems, don't need papers.