I need to build an app, can I do it all in Wappler?

1: I need Android and iOS. Do I need to build twice?

2: Ideally it would be able to serve push notifications to the user. Can this be set up in Wappler and what would be needed on the admin end to push the notifications?

3: I like using SHA256 for encryption of passwords. Will this work on mobile apps?

4: All data on the app will be served from a MySQL database which is administered through a web based dashboard. Both Android and iOS can be compatible with pulling data from a MySQL database?

5: Is there any other software I will need installed to be able to do this?

6: Anything else I should know that I possibly have not thought of?

Thanks!