Does iOS 13 has new way of getting device notification token?

You may use this method to fetch the device token on iOS 13 onwards:

Objective-C:

+ (NSString *)stringFromDeviceToken:(NSData *)deviceToken {
    NSUInteger length = deviceToken.length;
    if (length == 0) {
        return nil;
    }
    const unsigned char *buffer = deviceToken.bytes;
    NSMutableString *hexString  = [NSMutableString stringWithCapacity:(length * 2)];
    for (int i = 0; i < length; ++i) {
        [hexString appendFormat:@"%02x", buffer[i]];
    }
    return [hexString copy];
}

Swift 5.0 (Untested)

class func string(fromDeviceToken deviceToken: Data?) -> String? {
    let length = deviceToken?.count ?? 0
    if length == 0 {
        return nil
    }
    let buffer = UInt8(deviceToken?.bytes ?? 0)
    var hexString = String(repeating: "\0", count: length * 2)
    for i in 0..<length {
        hexString += String(format: "%02x", buffer[i])
    }
    return hexString
}

Taken from OneSignal blog

The same code for Swift 5 but bit shorter variant. Verified at iOS 13.

func getStringFrom(token:NSData) -> String {
    return token.reduce("") { $0 + String(format: "%02.2hhx", $1) }
}

The way you do it is fine and it should continue to work on iOS 13. But some developers do it like this. To convert Data into base-16 strings, they call description, which returns something like

<124686a5 556a72ca d808f572 00c323b9 3eff9285 92445590 3225757d b83997ba>

And then they trim < and > and remove spaces.

On iOS 13 the description called on token data returns something like

{ length = 32, bytes = 0xd3d997af 967d1f43 b405374a 13394d2f ... 28f10282 14af515f }

Which obviously makes this way broken.

Another example of wrong implementation (already edited to include correct implementation as well).

Some more examples might be found in this thread.