I just discovered an app called RapidCalc.I use this app on my iPoc Touch and together with a pen that gives me 0,5 units of rapid acting insulin this works really great.
You put your carb/insulin ratio and other stuff you know about how the insulin you use works for you into the app. Once you have done that the app works like a pump.
Before eating you measure your blood sugar, you put this number into the app, you put in the carbs you plan to eat and the app suggests the amount of insulin you should inject. At any time the app shows you how much insulin that´s still working in our body. The app also adjusts suggested doses according to planned excercise, previous lows and alcohol you´ve been drinking. You can read more about it here: http://www.gilport.com/rapidcalc/index.html
RapidCalc is compatible with iPhone, iPod touch, and iPad. It requires iOS 3.1.3 or later.
Do you know of similiar apps or other useful devices, feel free to post them here. Not everyone has access to iPhones, iPads or iPods.