IPhone going onto apple logo and then black screen when I try to turn on?

My iPhone has been really slow and freezing so I turned off my phone and then when I tried to turn it back on it just stays on the apple logo for like 20 seconds and then goes back off.

I've been fixing people's iPhones for years. Here's what I think you should do.

1) get in your car
2) drive to your cell phone provider's store
3) purchase the latest Samsung phone
4) problem solved

This solution someone has should fix the phone. Tho it will erase data on phone, just so youll know ahead of time---http://www.tipsninja.com/iphone-shows-apple-logo-and-shuts-off/