As you can see, I've replaced the dpad with four direction buttons:

Now I've started developing games, I've found that the dpad just doesn't work as well as I would like. The four direction buttons are better; the operation is smoother and it's easier to get the direction that you want.

So what was wrong with the dpad? I've used dpads similar to this one in other devices which worked well so what went wrong here? I think there are a few things:

• Rounding off the corners of each direction was a mistake. It looks nice, but it means that there is less surface area to press, meaning that your thumb has to be positioned more accurately.
• This device is much smaller than previous ones that I've built and although the dpad itself is about the same size as earlier ones, there is very little space below it. This means that you can't rest the ball of your thumb on the case and operate the dpad by moving the tip of your thumb up, down left or right. Instead you are forced into a bent thumb posture, where you lift and press on each individual direction. This requires more accuracy.
• Finally, in earlier designs I have used switches with a very short travel, the same ones that I have used for the pause and option buttons here in fact. These are rectangular and where I have used them in dpads, they were arranged with their short side facing the centre of the dpad. There was a small gap between the bottom of the dpad and the switches and a piece of foam rubber was used in the centre to stop the dpad rattling about. This time, I used rubber capped switches as I thought this would give the dpad a better feel. It did, but the function was much worse. As the dpad was now constantly in contact with the switches, pressing in one direction would apply pressure to the switches in the adjacent directions. This meant that if you weren't quite centred when pressing, for example, up, you would get up and left or up and right. I made a few changes to the dpad and was able to improve this somewhat but never got it to work as well as I wanted.

The result of these things is that you have a dpad that demands precise presses to behave correctly and anything else can result in it registering the wrong direction, which translates into a frustration playing experience. Splitting the dpad into four direction buttons was a quick fix that dramatically improved things. I think that there are for two reasons for this:

• There is no longer a mechanical connection between the directions, so pressing one direction cannot register spurious readings in the adjacent directions.
• Having four individual buttons provides better tactile feedback. There are more edges and so it is easier to register where your thumb is by touch.

Of course, the downside is that you can do things like press up and down or left and right together, but as hardware designers say: "we'll just fix that in software".