Sidemenu vs Tabs

We had quite the debate about either continue using the new Hamburger (side) menu or switch back to the good old tabs.

It seems that a group of people is not able to find the hamburger menu, but the design pattern frees some valuable real estate at the bottom and is much cleaner.

The advantage of using tabs is that all major screens are accessible with one click instead of 2.

We decided to use the hamburger menu for now, but to keep an open mind.

What is your opinion: Hamburger or tabs?