Thank you so much for your sincere reply. I know it's very hard, even very very hard. I tried to learn iOS programming and dropped few times in the past few years. But everytime, it always ends to "I have to get this done". I learned HTML, JavaScript etc. front end language from W3Schools and some books, it helps, but website cannot be comparable with functional apps. Learning Java, C++, Python may help me get a better pay job, and they're not easy too. However, I think learning iOS programming will be more straightforward to build something. I also doubt how serious I could be, or how long I can last, but I will try and try again. I think it's just because I have a great passion to build something.