Button position on bottom navigation

Question

I'm working on a redesign of an app with a tab bar for navigation. Currently, the main screen is the middle tab in the tab bar. The application is a few years old and already has a solid user base.

Many large applications that use the tab bar, keep the main screen as the first tab bar item. Think screens like "Home" (like the screenshots), or "News Feed" (like Facebook). Always on the far left.

My question is, is this design pattern so common that it is justified to switch the tab bar layout around? My users are familiar with the middle tab being the main screen of the app. Best practises seem to suggest the main screen should be the first tab in the tab bar.

Is there any research that shows that the tab bar item order helps improve usability and/or conversion? Or is it better to leave things as is, because my user's are used to that?

Answer 1

Ultimately, no, it doesn't make a difference, but there is an argument for having the home button on the left.

Left-to-Right Languages and the Concept of 'Returning' or 'Going Back' Home

Design conventions for left-to-right languages put things that happen in the past in a virtual space to the left, and things will happen in the future in a similar space to right.

Breadcrumbs are designed on this principle. As we navigate we develop a trail, the breadcrumb list get longer, and previous pages are to the left of our current one, with our source/root/starting page all the way on the left.

Answer 2

This might be all you need for bottom navigation guidelines...

I've come across the argument before that the middle button of a bottom navbar is more ergonomic (I can't remember where I heard it now). But I would also agree with what dennislees says in his answer.

Answer 3

The order of your tab bar items depends on which actions you consider primary, and which actions are less important and can be more 'out of the way'.

Home is often used as a 'reset' button; a useful tab if you need to return to restart or reorientate yourself if you get 'lost'. Especially in apps which rely heavily on discovering and searching content (YouTube, Instagram), it's convenient to have a way to get back to your personalised homepage. In a sense, it mirrors the bread crumb functionality; a recognisable trail back to a higher level.

The middle tab is very fit to be the primary task tab

The middle button is often reserved for frequently used actions because of its good accessibility regardless if you're left or hand handed, or have small or big hands. If your users are often going back to the main screen, you should consider keeping it easily accessed in the middle of the tab bar. If your main screen acts as a homepage that's more of a landing page than a frequently used action, consider moving it to the left and give room to an action that is often used.