If there is one thing you’ll always use on your phone it will be the keypad/keyboard whether it is a physical one or an onscreen version. I’ve always seemed to prefer phones with traditional keys (non QWERTY) as I like having the tactile feedback and also the ability to blind type. With the past 2 of my phones (Nokia 3110c, Nokia E51), I’ve had the issue that the keys are pretty hard to press (i.e. it requires quite a bit of force to press down) so after a long text message or instant-message chats, my thumbs would get tired. This led me to look into the ‘clickiness’ of keypads of phones as I was looking for a phone under $200 recently (with Bluetooth, card slot for music, a 3.5mm headphone jack & preferably 3G). I was pretty disappointed with the results and only found the Nokia 6303c had a nice ‘light’ keypad which buttons not requiring too much pressure to activate (The Nokia 3120c was pretty nice too but not as good as the 6303c).
There are several factors playing into the physical keypad of a phone: button spacing, button size, button placement and button activation pressure (as mentioned above). With all these factors playing into the keypad it made me wonder whether touchscreen keyboards would be better. Currently I have my sister’s HTC Hero and managed to play with a friend’s iPod touch recently. So I managed to get a good feel for both of them and here are some takes on their usability.
Initially the Hero’s onscreen keyboard was frustrating to me – especially in portrait mode. It made me think I had fat fingers and it was painfully slow to type and correct any mistakes. There is auto correct which does a pretty good job but when it comes to words that it doesn’t recognize it can get frustrating. First of all if you type a word, it will display several suggested words (which it thinks you’re typing) above the actual word being typed. If you press space (to move on to the next work) it will automatically use the word it thinks you’re typing. An example is if I want to type “Bsb” it will auto suggest “Van” and if I press space it will replace “Bsb” (that I typed) with “Van”. Now you can add “Bsb” to the dictionary and it will be recognized the next time but this can be annoying if you’re using acronyms or names of places or just a language that it doesn’t understand (e.g. Malay). You can use the onscreen keyboard in landscape mode which makes this much easier for thumb typing but I think the lack of multi-touch implementation (there is multi-touch on the browser with pinch zoom) on the keyboard phone prevents users from typing even faster. At at times the keyboard lags behind the typing so you get delayed typing. In my frustrations of the Hero I honestly wanted to get a Bluetooth keyboard or find a way to use a Nokia phone as a Bluetooth keyboard. Take note that the screen size of the Hero is smaller than the iPod touch / iPhone and makes the keyboard mode even smaller and harder to type on in comparison. After a few days with it, I’ve managed to make it more manageable but still I had better results with the iPod touch in the limited time I’ve had to play with it. Finally I have switched the keyboard mode to phone keypad which emulates the typical 1-9 button configurations with the appropriate letters as a normal phone with physical keys and it can toggle predictive T9 input on or off easily at the touch of an on-screen button.

I can honestly say that the iPod touch (and thus the iPhone) has a very good onscreen keyboard: Apple must have done great user experience testing and I have to say they have got it nearly perfect. The onscreen keyboard was large enough to type with both my thumbs in the portrait mode with few mistakes from the little time I had with it. I know that they have tweaked the keyboard making buttons ‘bigger’ based on which letter is more probable and this worked well for the words in English that I typed. I found that the auto-suggested word is just as cumbersome as the Android implementation: when typing a word that it does not understand, it will only show a single suggested word (as opposed to Android’s multiple words) and pressing the spacebar will auto-correct it to the word that it thinks you are typing. To prevent this, just tap the ‘X’ to close the suggested word panel. It didn’t seem that you could add words to the dictionary from normal text input which means you could get frustrated typing non-recognized words (you can add words to the dictionary via Safari but its a bit of a kludge).
On both on-screen keyboards I wasn’t too impressed with inputting symbols. Perhaps I’m just not used to it yet but I found it too troublesome and time consuming to type symbols. After playing with on-screen keyboards I still like physical keys and honestly I like the way Nokia has implemented the keypads on their devices along with the symbol selection. So in the meantime I will look for a Bluetooth keyboard on EBay to see if anything looks good.
Related Article: A good comparison on the virtual Keyboards on iPhone and Android