"Remember when mobile phones still had external antennas? Everyone thought they were annoying as hell, because, for example, you could not put your phone in your pocket upside down. Secondly, the antenna tended to break. Now, did I say everyone hated external mobile phone antennas? No, not everyone. Radio engineers liked them. And justifiably so: external antennas improve signal reception, improved signal reception reduces energy usage, which in turn improves battery performance.
Wired describes the struggle and compromises Nokia went through when tucking the 8810's antenna inside the phone (the case is part of a wonderful article called design under constraint). Nokia pulled some pretty smart tricks: they printed the antenna like a chip, gave the phone a shape that would lead the users not to cover the antenna with their hand, and they made part of the casing out of plastic (the rest of the phone was metallic).
Once again this shows the rocky road from concept to implementation. At one point or another most mobile phone developers could see consumers would prefer internal antennas. It was a matter of making it technically feasible, and being willing to compromise signal reception in favor of a product that's easier to handle. Because all other things being equal, a phone with an external antenna will always have better signal reception than one without, and thus better battery performance. However, when looking at today's mobile phones, we can safely say that users were happy to trade in some battery performance to lose the antenna. How technology, a smart design, and the right compromises can improve usability." (Continued via the product usability weblog) [Usability Resources]