Will using a iphone make you need glasses?

Or is using a computer worse. My dad says so and keeps taking my phone away lol.

Neither is worse than the other. Using electronic devices with a screen for long periods of time will mess with your eyes but that would be using for at least 20 odd hours a day.

Yes actually

Neither is worse than the other for your eyes.

No. Your dad is ignorant and paranoid. Computer screens and phone screens are nothing magic or evil, they are just a bunch of dots that form a picture. Show him some scientific studies. People are always afraid of technology. When the camera was first invented people thought it would steal your soul. People still think that electric windmills can give you cancer. Just explain it to him and show him that there's no logical reason *why* looking at a screen would damage your eyes.