Question

Can I invoke another installed applications within my application? Suppose I have installed AngryBirds, I have to invoke that application by tapping a button from my application. Is it possible?

Answer 1

You can do it if the application in question has a defined protocol, in example if you want to call a number via skype you can perform an action like

NSString *contactName = @"user123";
NSURL *skypeURL = [NSURL URLWithString:[NSString stringWithFormat:@"skype://%@?call",    contactName]];
if ([[UIApplication sharedApplication] canOpenURL:skypeURL]) {
    [[UIApplication sharedApplication] openURL:skypeURL];
} else {
    // Display to the user how to install skype.
}

the same can happen for other programs which have a protocol definition that could be understood.

And just 4 the record, here’s a list of know URL Schemes
http://wiki.akosma.com/IPhone_URL_Schemes

Then, if you want your app to be URL-Scheme Compatible, you can have a good start by reading this:
http://www.idev101.com/code/Objective-C/custom_url_schemes.html
and this other post is really good and detailed.

How do you set your Cocoa application as the default web browser?

it explains how to make your app handle a custom URLScheme, which turns out to be your case.

hope it could be helpful.

k

for other case scenarios I got no idea if it is possible.