Try Objective-C

Level1.m

NSLog(@"Harrison")
NSString *firstName = @"Harrison";
NSLog(firstName);
NSLog(@"Hello there, %@.", firstName);
NSLog(@"%@ %@", firstName, firstName);
NSString *lastName = @"Freni";
NSLog(@"%@ %@", firstName, lastName);
NSNumber *age = @16;
NSLog(@"%@ is %@ years old", firstName, age);
NSArray *apps = @[@"AngryFowl", @"Lettertouch", @"Tweetrobot"];
NSLog(@"%@", apps[1]);
apps = @[@"AngryFowl", @"Lettertouch", @"Tweetrobot", @"Instacanvas"];
NSDictionary *appRatings = @{@"AngryFowl": @3, @"Lettertouch": @5};
NSLog(@"Lettertouch has a rating of %@.", appRatings[@"Lettertouch"]);

Level2.m

//1
[tryobjc completeThisChallenge];

//2
NSArray *foods = @[@"tacos", @"burgers"];
NSLog(@"%@", [foods description]);

//3
NSArray *foods = @[@"tacos", @"burgers"];             
NSString *result = [foods description];

NSLog(@"%@", result);

//4
NSString *city = @"Ice World";
NSUInteger cityLength = [city length];

NSLog(@"City has %lu characters", cityLength);

//5
NSNumber *higgiesAge = @6;
NSNumber *phoneLives = @3;

NSUInteger higgiesAgeInt = [higgiesAge unsignedIntegerValue];
NSUInteger phoneLivesInt = [phoneLives unsignedIntegerValue];

NSUInteger higgiesRealAge = higgiesAgeInt * phoneLivesInt;
NSLog(@"Higgie is actually %lu years old.", higgiesRealAge);

//6
NSString *firstName = @"Harrison";
NSString *lastName = @"Freni";

NSString *fullName = [firstName stringByAppendingString:lastName];
NSLog(@"%@", fullName);

//7
NSString *firstName = @"Harrison";
NSString *lastName = @"Freni";

NSString *fullName = [[firstName stringByAppendingString:@" "] stringByAppendingString:lastName];
NSLog(@"%@", fullName);

//8
NSString *firstName = @"Harrison";
NSString *lastName = @"Freni";

NSString *fullName = [[firstName stringByAppendingString:@" "] stringByAppendingString:lastName];

NSString *replaced = [fullName stringByReplacingOccurrencesOfString:firstName withString:lastName];

NSLog(@"%@", replaced);

//9
NSString *firstName = @"Harrison";

NSString *copy = [NSString stringWithString:firstName];

NSLog(@"%@ is a copy of %@", copy, firstName);

//10
NSString *firstName = @"Harrison";

NSString *copy = [[NSString alloc] initWithString:firstName];

NSLog(@"%@ is a copy of %@", copy, firstName);

//11
NSString *firstName = @"Harrison";
NSString *lastName = @"Freni";

NSString *fullName = [NSString stringWithFormat:@"%@ %@", firstName, lastName];

NSLog(@"%@", fullName);