Tired of struggling to type numbers and/or punctuation on the iPhone's default QWERTY keyboard? Got a jailbroken handset? There's an app…er, hack…for that.
Coder KennyTM, previously known for his ?Clipboard global cut and paste hack, now brings you 5 Row QWERTY, which adds a top row of numbers to the default keypad; tap the Shift key, and the numbers are replaced by commonly-used punctuation characters. Dig a little further into the hack, and you'll find cursor keys to move through your document, page up/down and home/end control, tab inserts, even a "true" delete key. (Because man does not live by backspace alone…)
One caveat: to fit the new row of keys, KennyTM had to shrink the entire keyboard layout just a bit — so you sausage-finger types might have a rough go of it. Otherwise, this is the sort of thing that SHOULD be part of the iPhone, legitimately or otherwise. Go get it on Cydia.
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Phones having QWERTY keyboard are more saleable for business purposes. This is because it adds convenience to users.