How do I get the current version of my iOS project in code?

You can get the version and build numbers as follows:

let version = Bundle.main.object(forInfoDictionaryKey: "CFBundleShortVersionString") as! String
let build = Bundle.main.object(forInfoDictionaryKey: kCFBundleVersionKey as String) as! String

or in Objective-C

NSString * version = [[NSBundle mainBundle] objectForInfoDictionaryKey: @"CFBundleShortVersionString"];
NSString * build = [[NSBundle mainBundle] objectForInfoDictionaryKey: (NSString *)kCFBundleVersionKey];

I have the following methods in a category on UIApplication:

extension UIApplication {

    static var appVersion: String {
        return Bundle.main.object(forInfoDictionaryKey: "CFBundleShortVersionString") as! String
    }

    static var appBuild: String {
        return Bundle.main.object(forInfoDictionaryKey: kCFBundleVersionKey as String) as! String
    }

    static var versionBuild: String {
        let version = appVersion, build = appBuild            
        return version == build ? "v\(version)" : "v\(version)(\(build))"
    }
}

Gist: https://gist.github.com/ashleymills/6ec9fce6d7ec2a11af9b

Here’s the equivalent in Objective-C:

+ (NSString *) appVersion
{
    return [[NSBundle mainBundle] objectForInfoDictionaryKey: @"CFBundleShortVersionString"];    
}

+ (NSString *) build
{
    return [[NSBundle mainBundle] objectForInfoDictionaryKey: (NSString *)kCFBundleVersionKey];
}

+ (NSString *) versionBuild
{
    NSString * version = [self appVersion];
    NSString * build = [self build];

    NSString * versionBuild = [NSString stringWithFormat: @"v%@", version];

    if (![version isEqualToString: build]) {
        versionBuild = [NSString stringWithFormat: @"%@(%@)", versionBuild, build];
    }

    return versionBuild;
}

Gist: https://gist.github.com/ashleymills/c37efb46c9dbef73d5dd