CODEWITHSUNDEEP
iosiphone
GJain
GJain

Reputation: 5093

How can I detect if an iOS app is a new install or had been installed and deleted previously

How can I detect if an iOS app is installed for the first time or was deleted and re-installed?

I do use NSUserDefaults when the app is running. However, when the app is deleted, I believe all associated data is deleted.

My goal is to do SMS verification of the users phone number only when the app was installed for the first time on the device.

If for some reason, the app was deleted and re-installed, I want to avoid redoing the SMS verification.

What else can I do? Can I store some metadata related to my app which is not deleted when the app itself is deleted on the device?

Any standard pattern to follow?

Upvotes: 2

Views: 3275

Answers (5)

Garima Paliwal
Garima Paliwal

Reputation: 21

Try this code of storing your device code in keychain.....and keychain value remains the same even if app is deleted:

static NSString *serviceName = @"com.mycompany.myAppServiceName";
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
 NSData *passwordData = [self searchKeychainCopyMatching:@"device--code"];
    if (passwordData) {
        NSString *password = [[NSString alloc] initWithData:passwordData
                                                   encoding:NSUTF8StringEncoding];
        NSLog(@"pasword:=%@",password);
    }
    else{
        [self createKeychainValue:devicecode forIdentifier:@"device--code"];
    }
    //[self deleteKeychainValue:@"device--code"];
    return YES;
}

- (void)deleteKeychainValue:(NSString *)identifier {
    NSMutableDictionary *searchDictionary = [self newSearchDictionary:identifier];
    SecItemDelete((CFDictionaryRef)searchDictionary);
}
- (NSMutableDictionary *)newSearchDictionary:(NSString *)identifier {
    NSMutableDictionary *searchDictionary = [[NSMutableDictionary alloc] init];
    [searchDictionary setObject:(id)kSecClassGenericPassword forKey:(id)kSecClass];
    NSData *encodedIdentifier = [identifier dataUsingEncoding:NSUTF8StringEncoding];
    [searchDictionary setObject:encodedIdentifier forKey:(id)kSecAttrGeneric];
    [searchDictionary setObject:encodedIdentifier forKey:(id)kSecAttrAccount];
    [searchDictionary setObject:serviceName forKey:(id)kSecAttrService];
    return searchDictionary;
}

- (NSData *)searchKeychainCopyMatching:(NSString *)identifier {
    NSMutableDictionary *searchDictionary = [self newSearchDictionary:identifier];

    // Add search attributes
    [searchDictionary setObject:(id)kSecMatchLimitOne forKey:(id)kSecMatchLimit];

    // Add search return types
    [searchDictionary setObject:(id)kCFBooleanTrue forKey:(id)kSecReturnData];

    NSData *result = nil;
    // OSStatus status = 
SecItemCopyMatching((CFDictionaryRef)searchDictionary,(__bridge CFTypeRef *)&result);
    OSStatus status = SecItemCopyMatching((__bridge CFDictionaryRef)searchDictionary,
                                          (void *)&result);
        return result;
}

- (BOOL)createKeychainValue:(NSString *)password forIdentifier:(NSString *)identifier {
    NSMutableDictionary *dictionary = [self newSearchDictionary:identifier];
    NSData *passwordData = [password dataUsingEncoding:NSUTF8StringEncoding];
    [dictionary setObject:passwordData forKey:(id)kSecValueData];
    OSStatus status = SecItemAdd((CFDictionaryRef)dictionary, NULL);

    if (status == errSecSuccess) {
        return YES;
    }
    return NO;
}

Source

Upvotes: 1

Cường Trần
Cường Trần

Reputation: 19

I think, you send UDID to icloud Apple to store it. If app install first time. Icloud iphone not found, else It will have UDID. You need't server.

Upvotes: -1

Patrick T Nelson
Patrick T Nelson

Reputation: 1254

There is no way to accomplish this with iOS alone, but you could achieve this by having a server with a database, and the first time the app is run you send the device's UDID to your server; if the server already has the UDID, then the app was already installed.

Of course this solution does require the user have an internet connection.

Upvotes: 0

mandeep-dhiman
mandeep-dhiman

Reputation: 2535

You can use keychain and keychain does store values after we uninstall the app.

Apple has provided KeyChainItemWrapper class in their GenericKeyChain (sample code)

Upvotes: 1

Dave Wood
Dave Wood

Reputation: 13333

You can do this by storing a value in the user's keychain. It will persist even if the app is deleted and thus you can tell if the app is a new install or a reinstall. Add another value to the user defaults for comparison, if both values exist the app has been installed and executed at least once. If neither values exist, it's a new, first time install. If just the keychain value exists, it's a fresh reinstall.

Upvotes: 4

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