Mobile Phone Numeric Keys

I noticed that recent mobile phones have numeric keys that are positioned close to one another (see first 2 pics). These phones are difficult to use, as users are predisposed to depress a wrong key or depress two keys together.

Space constraint should be the reason for mobile phone designers to cram the numeric keys together. Nonetheless, is there no other way to solve this problem besides increasing the phone size?

One of my friends, Mr Aloysius Liow, suggested a clever idea to solve the problem: reduce the size of every key. This will create space around each key, which will decrease users’ tendency to depress adjacent keys. Such design can be found in most PDA phones and BlackBerry (see last pic)

Actually I do have some problems with my phone keys. it's not rare that i press the wrong key as they are positioned pretty close to each other.

I'm still using the retro kind that has smaller screen, and hence there are spaces between the buttons. Maybe it's not a good idea to upgrade our phones?

Actually i don't really agree that leaving spaces in between the keys solves the entire problem. Nowadays, phones are getting smaller with larger screens, leaving little space for keys and with this contraint, having spaces in between keys may result in very small keys which are hard to press also. I personally feel that the problem with key pads nowadays is that there's no differentiation between the keys (see the pictures in YSL's post). The keys are shaped the same and "feel" the same. This provides no tactile feedback when the keys are presed. By simplying adding texture to the keypads, you'll be able to feel which is the key you want and less errors should be made.

For example, my phone, Samsung E530C has keys which are connected together, however the 5 and 8 keys are protruded so i can tell by feeling the keypad (without looking) which key i want to press and i seldom have problems of pressing the wrong key.

Actually I prefer old-phone's numeric keys... eventhough it might not easy to press the button... but at least they have a well-designed space between keys

for example nokia 3310

JohnTuckerMustDie wrote:

Actually I prefer old-phone's numeric keys... eventhough it might not easy to press the button... but at least they have a well-designed space between keys

for example nokia 3310

Ya, I also prefer old-phones. Besides being easier to press, they are not as complex. Some new phones contain features that are not useful and take a long time to load. Maybe phone development time can not cope with consumers' demand for new phones?

This brings us back to the basic HF concept. Increased functionality does not lead to increased usability. But how does one do a trade off between functionality and usability?

Trade off between functionality and usability?

Yes, I agree that increased functionality does not lead to increased usability, but I don't think increased functionality will necessarily lead to decreased usability. More useless functions will decrease usability, but more useful functions will increase usability.

How can we effectively screen useless functions and yet formulate an exhaustive list of useful functions?