Freebbble!

Download for free, do whatever, just don’t sell. This is just a very rough estimate, not really a final product.

Flat Bank UI is a free UI design resource made by Dribbble user Rishabh Varshney. As far as I can tell, its license is Free for Commercial and Personal Purposes.

Helpful hint: Dribbble users are nice. If the license is unknown, it is usually because they forgot to mention it explicitly; not because they were being stingy. Ask nicely and they will probably allow you to use it.