Adding multiple strings in to an array one by one and Saving-iPhone

 //in .h
NSMutableArray *amountSpend;

//in View did load

NSArray *path1 = NSSearchPathForDirectoriesInDomains (NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory1 = [path1 objectAtIndex:0];
NSString *fullFileName1 = [NSString stringWithFormat:@"%@amountSpend", documentsDirectory1];

amountSpend=[[NSMutableArray alloc]initWithContentsOfFile:fullFileName1];

if([amountSpend count]==0){
amountSpend=[NSMutableArray alloc]init];
}


//action when the data need to be saved

[amountSpend addObject:amount.text];
NSArray *paths = NSSearchPathForDirectoriesInDomains (NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];


NSString *fullFileName1 = [NSString stringWithFormat:@"%@amountSpend", documentsDirectory];
[amountSpend writeToFile:fullFileName1 atomically:NO];