Please please keep important buttons at the bottom of the screen

With Windows 10 around the corner, it seems a good time to issue a plea to keep buttons reachable.

Phone screens are getting bigger, but thumbs aren't.

Please, please keep important app buttons - like settings, send and so on - at the bottom of the screen.

If they're at the top - like Microsoft appears to be doing with the "hamburger" settings button in Windows 10 email - well, we can't reach them using the phone one handed.

So keep them at the bottom and make it useable.