Hello all,

so i decided to play around with iphone but i already have a 3G powered phone, and iphone here is the 3 times the price of ipod touch. What i am asking is what is the main diffrences between ipod touch and iphone apart from camera, phone features and 3g. I believe my app will work on both, and i can dev on a ipod touch. What is the diffrence between their system software? keeping in mind that i already have a 3g phone, does it still worth buying iphone?

or should i dump iphone dev ideas and wait for ipad?

Short answer: You probably need neither of the two. If all you want to do is develop software for the iPhone/iPod Touch, you only need a Mac + XCode + the iPhone SDK.

Long answer: The iPhone SDK provides everything you need to test your application, but there are things to consider: the iPod Touch is slightly more powerful while the iPhone has features like GPS that have only limited support on the iPod Touch. But it really doesn't matter which one you use for development. If you already have a 3G phone, go for the iPod Touch or only the simulator on the Mac. Remember though that you cannot develop apps without a Mac. And in order to get your apps onto the device you need to pay as well.

As far as I know, the firmware of both is identical, but you will have to pay for major firmware updates for the iPod Touch, at least if aren´t a developer as if you are, you can at least download beta versions, I am not sure about the release versions though. I also think that the hardware of the latest iPod touch is a bit better than the hardware of the iPhone 3GS.
If I understand it right, the iPad also uses the iPhone OS, so that you can just get an iPod Touch and develop for iPod Touch, iPhone and iPad. But as for example the screen dimensions of the iPad are different as it is 4:3 what the iPhone and iPod Touch isn´t, you should may get an iPad as well if you somewhen decide that it is worth it. But I think for the start the iPod Touch is a good choice, even though I like my iPhone quite a bit

thanks for the answers! i already have the mac and xcode ready. For the dev license ($99?) do i need it in the begining or i only need it to get my app on the device and distrubite it?

You only need to pay the $99 if you want to distribute your app over the AppStore or if you want to get your app onto devices. See this website for more information:

http://developer.apple.com/iphone/program/apply.html

You cant develop a polished game without the device to test it.
Emulators only partly represent the game/apps in action.

For development, the IpodTouch should be enough, if
you limit it to these features.
Also using the slowest device is good for
development to see perfromance glitches.
There might be some minor differences with the
different OS versions, but nothing you
need to bother at the start of your app development.
Its still good to have some frineds with other iPhone versions
to testcheck though.

This isn't even a emulator, its a simulator with its own binaries.

The SDKs are the same, so iPad, iPhone and iPod Touch can use the same APIs and the OS will prevent you from doing stuff you can't do on one of those devices (the iPad for example can't show a transparent menu bar).
I have just "converted" an App from me for the iPad, by converted I mean: Just change the position of the elements to fit the screens. It's really easy and took five minutes, here is a screen:
http://img5.imagebanana.com/img/3quyfvvi/Bildschirmfoto20100128um14.58.55.png

The same App can run also on the iPhone and iPod Touch without a change!

then i will probably start working with the simulators currently, i am new so it will take some time for me to learn detailed stuff. If iPad becomes available at the point i wish to try my app on a device, ill go for ipad if not ipod touch.

thanks again everyone.

You can use the SDK for learning the basic stuff.
When it comes to tuning user-inputs, memory use and performance
you should have a device available.

The iPad will take some time to reach a bigger market
share. But it can run iPhone apps from the start.