Well, I don't claim that my daughter is a super-genius using Mail or Safari for her baby needs - of course I mean the apps that were (almost*) designed for the toddlers like her.
She can't speak yet and she is not precise enough even for many apps meant for the youngest babies, so the choice was actually limited to the really simplest apps.
Her favorite were the ones where she could scroll animal pictures with her finger.
Almost is not EnoughAt least in UX design for babies :-)
The apps I found for her had beautiful pictures and were generally fine, but she had problems using them.
She really wanted to grab the phone by herself, not play with her dad holding it. However, she would always grab the phone with the thumb resting on the screen, which made the standard UIScrollView based apps unable to scroll with the other hand. The more I tried to teach her to hold the phone in a different way, the more frustrated she got and the less fun there was for both of us.
Another problem was that all the apps had some active parts not meant for scrolling - settings, show picture description, back to menu or other stuff which is probably very useful for adults or older children, but not for a baby (who, as studies have shown, can neither read the description nor effectively avoid activating the buttons ;-) )
Do it Yourself...if you want it done, especially if you want it done now ;-)
After observing how my 1.5 year old daughter tries to use the apps, and seeing how the should actually work I decided to write my own.
Overcoming the two-finger scrolling problem was the toughest part, esp. that I could not find any solution on the Internet. Having to learn Objective-C hasn't made it easy, too. Obtaining developer certificate from Apple that would allow me to install my app on the phone maybe wasn't hard, but it took longer than I expected - the whole process took more than 1 week.
Selecting almost 40 nice (Collective Commons) pictures out of over 6000 available on AnimalPhotos was a nice whole-evening family exercise :-)
Seeing my daughter play with the Toddler Zoo app I wrote for her is just priceless.
If you also have a baby and an iPhone (or someone you know does), the app is available in the iTunes store.