There are many problems in this. You should know that Nokia's application development is not as easy as Android and Apple. Apple has an app store because its system is closed. It costs money to download and install a lot of software in his home. You said that developing a program is easier than Nokia, and it can also make money. Who will develop Symbian software? Android is because the system is too open. Many people can't make money on software, but they can make money on other things. This Nokia installation software also needs to be signed. This is also related to Nokia's last CEO in Troy. Because Microsoft needed an excellent software and hardware manufacturer, he turned his attention to Nokia. Many good Nokia systems were abandoned and accepted by Microsoft. However, Microsoft wp system is not strong.