For sure, TK-421 has a few major advantages over ProMini. starting with a $20 lower price tag, continuing with larger Chiclet-style keys that are physically separate from one another, and ending with a design that not only fits directly into the iPhone 4’s footprint, but actually encases the phone while swiveling out from underneath it. TK-421 nearly doubles the iPhone’s thickness, but it’s much smaller than ProMini and dispenses…
