So you're wondering, why the iPhone 4, the dinosaur that it is today, would be considered the "best" design Apple has ever made. There are actually very good reasons why. Here are just 4 that I can think of.
1. Glass is perfect for antennas and wireless signals.
Glass is almost invisible to wireless signals. It creates little to no interference and allows more freedom for antenna placement inside of a device mostly surrounded by metal and battery. When aluminum is used for a phone's body, it significantly reduces its signal range. Thats why the iPhone 6 though the iPhone 7 had "antenna lines" on the body of the phone. This also explains why many Android phones skipped metal all together and used plastic. The iPhone was a glimpse into the future where phones would have multiple antennas, and now wireless charging. The iPhone 8 borrows from its grandfather with the new "glass sandwich design" for this reason.
2. Glass and metal always look premium.
I don't know about you but when I saw the iPhone 4 for the first time, I was shocked. I was thinking "I've never seen a portable electronic device made of 80% glass". People even made fun of it saying it was crazy to make a phone made of mostly glass. I feel that this design is timeless, almost like an expensive old watch. Several phones have borrowed this design, most notably Samsung with their S8 and S8 Plus. Really just about any device using this design gets rave reviews of its aesthetics. Too bad there's a major tradeoff. Breakability is doubled with a glass sandwich design and in some cases, doubling the repair cost when broken.
3. Glass allows easy and cheap customization.
For technicians who have repaired many iPhone 4's, you know that since the back glass comes off with just removing the bottom screws, that allowed easy customization for the first time in an iPhone. Kind of like the Xbox with the removable face plates, iPhone 4's could have any combination of designs or colors on the back. If you broke the glass, you could swap it out for another one with ease. Now that phones glue the back glass on, it makes customization much harder. But the fact remains, you can still change colors without dismantling the entire phone to do it. With the iPhone 8, I can assure you that people will start customizing their phones again.
4. Glass is harder to scratch than metal.
Surprisingly, glass does not scratch as easily as metal. While anything can get scratched with normal use, glass often times stood the test of time better than even plastic. Sure, plastic or metal won't crack after dropping it an inch off the ground, but if you are careful (like me) and never drop a device, you get to enjoy actually using the phone without a case. My iPhone 4 had very few scratches and i didn't really use a case. My iPhone 6 gets scratches just from the case being on the phone. And don't even talk about the iPod touch 2nd through 4th generation models. They got scratched just by you breathing on it. Even my stainless steal Apple watch has scratches all over it and its basically just rubbing against my shirt sleeve most of the time.
I like the iPhone 4. Not the size of the iPhone 4, but the glass design. Very elegant and minimalist. I'm glad Apple has decided to make the iPhone 8 and the iPhone X return to its roots, design wise for the simple fact that nothing can top the function and versatility of glass.
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