check out iAppWorld.net site and also the iAppWorld.net appstore free app ... its really cool
It may not be free unless you already have a mac if you do then you need to go to the apple website and download the iPhone sdk... programming knowledge is required(objective-c) if you're on a PC then you would have to either buy a mac(not so cheap), develop jailbroken iPhone apps free, i think, (but less people will know about it since the jailbrake community is pretty small compared to the total number of idevice users), or make a web app not free as it will be the same as building a web site(you would need to buy a domain name, pay a web host to get the website up and running and you will need to know web design languages like HTML, CSS, Javascript and some others this part is free.
by app store
You can make an app for the iPhone for free (or almost free), however there are already multiple loan payment calculator apps for the iPhones. You may still choose to make another one if you want.
Cycorder is your answer. It is free but require that you jailbreak your iPhone.
Booty Book is my favorite. Its in app store under "B Book".
free games for my iPhone
check out the iappworld.net free iphone app on the appstore
download 'skype' from the itunes store, its a free app and you can make phone calls off of it so long as you got a wi-fi connection
There are many of free news apps on the iPhone. Some of the top news apps are APMobile, The New York Times App, and NPR News iPhone App. You can find these in the App store.
use iappworld.net site, or free iphone app, and download apps and games for free :)
Yes, there is a free App to play solitaire game on your iPhone. You can go to the App Store and download a free version.
Yes, you can find your lost iPhone with an iPhone app. However, you must have access to another apple product with the same app to locate your lost iPhone. It's called FindmyiPhone in the app store, and it's free. All you do is make an account. Let's say your iPhone is lost, all you do is sign in with your account with another device with the same app and the app will do the rest. Its quite amazing.
Most are really free (with lots of ads) but some require you to make in-app purchases in order to be able to the game, making it a payed game.