UIAlertView for user to download another app - objective-c

Question

I downloaded an app from app store and noticed that once I installed and opened the app, I got a UIAlertView suggesting that I download another app..
How can I achieve this? Are there any existing code that I can be directed towards?
Seems like a simple feature but I'd like to integrate it. Please see attachment
Here is my edited code, but the 'Hello' button won't link anywhere.. What am I doing wrong?
UIAlertView *message = [[UIAlertView alloc] initWithTitle:#"Hello World!"
message:#"This is your first UIAlertview message."
delegate:nil
cancelButtonTitle:#"OK"
otherButtonTitles:#"Hello", nil];
[message show];
- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
NSString *title = [alertView buttonTitleAtIndex:buttonIndex];
if([title isEqualToString:#"Hello"])
{
[[UIApplication sharedApplication] openURL:[NSURL URLWithString: #"https://itunes.apple.com/gb/app/islam/id667021108?mt=8&affId=1930871&ign-mpt=uo%3D4"]];
}
}

Answer 1

first you have to make alertView, if you want to show the alert as first thing but this code inside (ViewDidLoad) method
UIAlertView *alert = [[UIAlertView alloc]
initWithTitle:#"your title"
message:#"your message"
delegate:self
cancelButtonTitle:#"Not now"
otherButtonTitles:#"Download now"
, nil];
[alert show];
after viewDidLoad but this method
- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex {
if (buttonIndex != [alertView cancelButtonIndex]) {
[[UIApplication sharedApplication] openURL:[NSURL URLWithString:#"here but your application link"]];
}else{
}
}
//=================================================//
To know what's NSUserDefaults, I suggest to take a look the official doc.
And of course you can use it to fulfill your goal. You use a user default to store information about the current amount of runs in the app.
More or less like:
BOOL NotTheFirstTime = [[NSUserDefaults standardUserDefaults] boolForKey:#"NotTheFirstTime"];
if(!NotTheFirstTime){
// Show the alert view
// Then set the first run flag
[[NSUserDefaults standardUserDefaults] setBool:YES forKey:#"NotTheFirstTime"];
[[NSUserDefaults standardUserDefaults] synchronize];
}
if that help you please make it the best question.

Answer 2

It is pretty simple:
1) Set up an UIAlertView as usual with the text and the button titles you like.
2) Set up the UIAlertView's delegate and use this method to figure out which button was clicked (whether the user does or does not want to go to the App Store):
alertView:clickedButtonAtIndex:
3) If the user wants to go to the App Store, open up an App Store link:
[[UIApplication sharedApplication] openURL:[NSURL URLWithString: #"<#This is your App Store Link#>"]];