When we sat down to design the user interface of SanDisk’s new iXpand app, we knew we needed to make sophisticated, complex software that felt simple and intuitive.

The problem that SanDisk was out to solve with the iXpand was a universal one: Though our smartphones have become an integral part of everyday life, they never seem to come with enough storage. A 16GB iPhone can only store about 2,000 photos, and live photos cut that number in half, and 4K video can eat up a 16GB hard drive in no time. It’s just not enough for the modern iPhone user, who is taking 20% more photos each year than they did the year before.

Given that the storage space on the iPhone isn’t expanding at a rate that matches the modern consumer’s increasing storage needs, SanDisk stepped up to fill the need with a flash drive that included software with easy to use, and sometimes even automated features that make it easy for users to back up (and access) their media quickly whenever they needed to. With iXpand we set out to update the design used on SanDisk’s iStick.

For the iXpand, though, the design needed would work for two very disparate extreme users — the tech savvy traveler who has high demands and little patience for poor UX design and slow transfer speeds, and the older tech novice who’s looking for a way to free up space without all the fuss that goes along with learning the ins and outs of new software.

For the tech novice user

We made the introduction simpler, with a clear order to onboarding. The old welcome screen read “Drive Not Detected” in large font if a user loaded the app for the first time without having the accompanying hardware already connected. For someone already uneasy with technology, this could create a sense of early apprehension or frustration before they’ve even used their brand new product. So we redesigned the welcome screen to, first and foremost, welcome the user to the app and then in smaller text below, help them connect the hardware before moving on to the next step. This way they know that nothing’s wrong, they just need to make sure everything’s in place before they can go to the next step.

When it comes to the tech novice, you have to constantly remember that they’re new to much or all of this. Nothing about operating software will feel simple or easy to them, so the more you can give users clear, defined actionable, the better their experience will be.

This was a big part of our decision making process in redesigning the interface for a tech novice. While the old software used arrows to point out features, we opted for a step by step introduction with swipeable cards. We gave users a clear introduction to the app, and helped them find the features they were looking for without unnecessary distraction.

We also redesigned the way permissions are acquired in order to reassure users who are nervous about privacy. By creating a branded SanDisk pre-permissions screen, users are first made aware that the app needs to access their photos by the app itself, before iOS’s obligatory permissions screen pops up. This way users don’t misinterpret the situation and think the app is trying to covertly access their private information.

For the tech savvy user

At the same time, we were also designing for the opposite user type. The tech savvy user is looking for a quick, painless onboarding process; an intuitive user experience; and lots of control. This might seem like an easier user to design for, but often it’s the opposite.

Tech savvy users might have an easier time navigating apps, but only if the interface is designed in a way that follows the rules the user already knows. For instance: Thanks to apps like Tinder, most tech savvy users already know that swiping right is like saying yes or next swiping left is no or go back. It’s a gesture based in intuition to some degree, but cemented by a few popular apps. This rule is so established that a tech savvy user would likely get frustrated with a app that used a left swipe for next.

This user has a lot of experience with software, which can work to a designer’s advantage, but it can also work against you because this user is highly demanding and short on patience. Tech savvy users often want to skip the walkthrough. In this instance, there was a prompt to start an auto backup immediately after the initial walkthrough. Several testers tried to skip the first auto backup simply because it came so close on the heels of the walkthrough they thought it was all a part of the walkthrough and were eager “get started” with app. This user often assumes the walkthrough will be full of obvious information that they already know or can figure out quickly as they navigate the app.

We constantly reworked the UX interface to find ways to keep them engaged and learning the app without feeling controlled or bogged down. Every informational card or popup came with something actionable. They were given something to do with that information immediately.

To satisfy some of the tech savvy user’s desire for iXpand, we also built extra features like a simple, drag and drop playlist creator. Any user who’s used another app to build playlists will instantly know how to add files, rename the playlist, and reorder songs. But it offers another level of usability and lets the user feel that sense of control and versatility throughout the experience.

Finding the common ground in UX design needs

While there are a lot of things that these two users differ on, there are a few features they both demand. Great, intuitive design is key. Tech savvy users already know (or think they know) the basic rules of software — they expect to be able to intuit how to use the software without having to read any instructions or follow a tutorial. While more novice tech users don’t tend to take that approach, their lack of comfort with software can make them easy to scare off or confuse.

This meant the new software UX design had to be more visual than its predecessor. Where the older version, the iStick, had a more minimalistic approach to visual design with long lists of file names and no thumbnails for images, we dispensed with the filename lists and made the whole experience a visual one with plenty of thumbnails and larger icons.

Neither the tech novice or tech savvy users were getting much out of the passive infographs that appeared in the app to inform users of available drive space or remaining battery life. It’s not that the information wasn’t important — it absolutely was — but it was simply being presented without any apparent next steps for the user to take to address the issue. For tech novice users, that was confusing, for tech savvy users it just came across as unnecessary information to dismiss. So we swapped out the infographs for actionable cards with prompts to make it easy for users to understand the issues and solve it on the spot.

While extreme users can have very different needs, they often have more in common than you might realize. Designing for them involves thinking through each step like the individuals and then as a group. It requires the ability to strip away any rules or processes that seem obvious, and start from scratch. Every time an action or a screen comes back with mixed feedback, you have to back to the drawing board to rethink the process. Designing for extreme users isn’t easy, but when you finally get feedback from users of all ages, experiences, and walks of life telling you they were able to navigate the app with ease and get the most out of the features — it’s a great feeling.