An artist’s render of what he hoped the Samsung Galaxy S4 would look like. An aluminum frame with a soft skin battery cover for a case back.
The Samsung Galaxy S4 is one amazing phone. It has a large, sharp and vibrant display. It is blazingly fast. The camera on the Galaxy S4 is about as good as they get. Internal storage is expandable. You can even replace the battery. It has won awards for having low SAR ratings and being easily repairable. It was obviously designed by excellent engineers.
Despite all these pluses, in the eyes of many consumers, and even tech writers, it has one big flaw. It is made of plastic. And there is the rub. Yes, the Samsung Galaxy S4 was designed by an excellent team of engineers.
Now, I am all in favor of plastic, but I can understand the disappointment. After four generations of flagship Galaxy S4, you would think Samsung could find a nicer looking plastic material to use. Nokia did a good job with the “polycarbonate” (i.e. plastic) Lumia 800 and 900. No one made an issue of the HTC One X being made from plastic (i.e polycarbonate). The BlackBerry Z10 also has a plastic case, and no one seems to have taken it to task for that. Samsung really could have used nicer looking plastics. In fairness, the current plastic, which it calls “hyper-glaze”, looks premium enough in a color like grey. But it does not fare too well in black, pebble blue or white. What a lot of consumers really want is an all aluminum Samsung Note III and Galaxy S V.
Exactly when and why aluminum became a premium material for mobile devices, I don’t really know. Aluminum is easily scratched, dinged and dented. It has never been considered a precious metal. Actually, it is what is used to make the can of soda I am sipping from.
My fondness for plastic is based on my own experience with aluminum phones. A few years back when I selected my first android phone, the aluminum unibody of the HTC Desire HD was a big part in the decision making process. It looked great.
I quickly learned that aluminum was not a good material for building mobile phones. On my first day with the phone, I noticed that WiFi reception was significantly poorer than the plastic phone it replaced. I got no reception from a spot where I had been getting a decent signal. Now, the HTC Desire HD houses the WiFi radio on the right side of the phone, integrated into the back of a plastic battery cover. I notice if I oriented the battery cover towards the direction location of the router, I would get a good WiFi signal. Orient it differently, and the aluminum unibody gets between the router and the WiFi antenna killing the signal.
Aluminum affects radio signals. All materials have an Attenuation Coefficient. Water, cardboard, paper, wood, brick, cement, clear glass, and most plastics have low attenuation coefficients. Radio waves reflect from these materials, and more importantly, easily pass through them. Metal, metal-coated glass, steel-reinforced concrete, copper and aluminum, reflect most of the radio waves, allowing very little, if any to pass through.
It is no coincidence that phones that have been reported as having “death grip” issues are constructed partly of aluminum. The “death grip” is the term used to describe the loss or reduction of signal when holding the phone in a certain way. The Apple iPhone 4 and HTC Sensation were both reported to suffer from the death grip. Even when you build the phone’s antenna in a location so as to minimize the effects of aluminum reflecting radio waves, it still does have an effect whenever the aluminum parts get between the antenna and the source of the radio energy. This can also contribute to heavier battery drain.
Other than plastic, there are other options for constructing a phone with more premium materials. Motorola used Kevlar on some of its phones. The other solution is to sandwich a rubberized or plastic material between two pieces of glass, like you see on the LG-built Google Nexus 4 and Sony Xperia Z. The problem with glass is you have to design something with a flat back and it adds to the weight. This is something which goes against the engineering philosophy behind the curved backs and light weight of Samsung’s designs.