Truth is typing on a slab of glass just isn't efficient. Even with the larger iPhone 6 plus, iPad mini or Ipad Air 2, typing is acceptable at fast. Typing on glass is much slower than typing on a traditional keyboard (because of the tactile response which means you don't have to look at the keyboard). 

Over the last 20 years, I have tried hundreds of portable keyboard and only a small handful have actually been "good" or usable in the field. Now a company called WayTools is launching a brand new ultra compact portable bluetooth keyboard called the TextBlade. [Since it is bluetooth, it works with all modern smartphones and tablets including iPhone, iPad, Samsung, HTC, Nexus and more).

Announced at CES, it is a 3 piece keyboard that magnetically attaches to itself. It charges using any USB port and the company claims you get 1 month of autonomy with a 1 hour charge. 

The company describes the TextBlade as:

WayTools TextBlade uses the same QWERTY layout we all know and love but adds smart functions like copy/paste, easy letter, word or sentence selection, etc.

I can't judge it until I test one for a couple of weeks but I am very much interested and intrigued. If this works as advertised, it may turn out to be a huge win for the company and mobile productivity nuts.