Simple's logo has been designed with "responsiveness" in mind: the more space they have, the more complex their logo is.<p>For example on <a href="https://www.simple.com/" rel="nofollow">https://www.simple.com/</a>, the logo in the header is simpler that the logo on the credit card.<p>They also show the 3 versions they use in a blogpost: <a href="https://www.simple.com/blog/simple-branding" rel="nofollow">https://www.simple.com/blog/simple-branding</a>