User experience issues when the order of content changes?

Question

I'm working on an iOS project for users with age 55+ years who have not to much experience in using mobile devices.

I have around 8 tiles with information to show the user. (Scroll View)

By time some of those information are more relevant to the user so I want to sort / rank those tiles dynamically.

My question is, how confusing is it for a user, especially an unexperienced / old / not digital native user :D that the order of the content changes every now and then.

I know form my grandma that if she searches for something in an app, she doesn't remember how to get somewhere by logical thinking, she actually tries to remember the exact location like "View XYZ" and then scroll down X cm / inches. So I could imagine that those users get irritated if the content order / location changes -.-

What is your opinion and experience on that?

Answer 1

A user's spatial memory is sensitive, and moving items can also be the same as removing them.

Spatial memory is what we use to navigate the world, and it means that once we find something in an interface, we tend to remember where it was rather than how we found it. Accessing the spatial memory of its location is faster than repeating the cognitive process of finding it each time.

Combined with the serial position effect, this means that your users are very likely to remember that the item they cared about was at the beginning or end of the list, and on repeat uses they will likely jump right to the item in that position before they read it and mentally process what it says.

That means that moving things on your users is usually a bad idea. What makes it worse is that due to the age of your audience and their limited experience with technology, they may not realize that things have moved. In your example, if they are expecting the left screen but instead see the one on the right they may conclude that tiles 2 and 3 have been deleted rather than moved. Or they might think this is the wrong screen/page because nothing looks familiar. This demographic has a reluctance to explore interfaces unless they know exactly what will happen, so asking them to go searching for a tile that may or may not exist won't be painless.

You'll have to decide if the benefit of reduced scrolling is worth the confusion that will be encountered each time things move. Only user tests with your target audience can tell you for sure if that tradeoff is worth it. Additionally, those tests might also tell you which tiles are the most important and you can put them at the top for everyone before launch.

Two other scenarios that might change this answer: how frequently is the app used, and who will be setting it up the first time?

If the app is used rarely (once per month or less) users will probably forget where anything was between each use and will have to re-find things each time anyway. In this case, the pain of moving things is greatly lessened as each use is almost as fresh as the first time.

If the user isn't likely to be the one setting up the app, you have additional options. Being able to flag or favorite tiles would allow the person (child, grandchild, caregiver, etc.) getting the app configured the ability to select the most relevant tiles, and pin them to the top of the list which would completely skip the need to move things around on the actual user later.

Further reading: Spatial Memory, Serial Position Effect

Answer 2

First of all i am a fan of your approach, 8 tiles linear navigation i envy the simplicity.

Second I have to clear-out my responsibility to this question as you have not indicated the purpose of the tiles, i am assuming those tiles provide nice informative value such as the weather and such, so nothing of high impact like emergency calls or health related information etc...

---

One technique you can consider is a better global order through analytics, statistically whats the most-least frequent tiles your users use, with this one you can benefit with one of two ways:

The obvious one

Most frequent on the top to least frequent on the bottom of the list, this one causes your users to easily access the most frequent tiles.

The dangerous one

You could go with a crazy idea that is the absolute contrary of your original proposal:

Least frequent on the top to most frequent on the bottom of the list - controversial but hear me out first.

The disadvantages of "The obvious one" comes with hiding the less frequent tiles, meaning the user might not realize their existence or simply forget about them.

This way you would ensure that the user will use the scroll frequently and occasionally notice what is provided while scrolling down, therefore not missing out since you have just established a frequent behavior.

I have to make a disclaimer here though, do not mess with the seniors you better be knowing what you are doing before you commit to this one, so keep in mind it wouldn't work for example with non-frequent users or users with memory struggles, but now comes the real question:

Why do you need to change things?

---

Do you have a good reason to do so? The way i see it, it's not a huge content platform it's 8 tiles, the most successful scenario for your sorting is bringing tile #8 to #1 is it really needed? Are your users struggling with finding the tiles under the screen or you just want to make things more reachable?

If it's the 2nd answer then you really don't need to, i don't have much work experience with seniors but i have in my life and from there i can safely say it's much harder for seniors to learn and adapt to change, rules, and concepts (such as sorting, or how the sorting works etc...) than learning things as is or as steps as you have mentioned (navigate down, you find tile 8).

If the users are indeed struggling with the findability and reachability of the tiles, there are things you can do let's break things down a bit:

Change order by relevance

• Yes, we can introduce manual ordering (requires learning, increases interaction space)
• Yes, we can introduce automatic ordering (confusion & complexity)

Is it possible to show all of the tiles in a single view?

• Yes, we can reduce the content size (create accessibility issues)
• Yes, we can eliminate some of the tiles content (reduce added value)
• Yes, we can eliminate some of the tiles themselves (defeat main value)
• Yes, we can introduce hierarchical navigation (confusion & complexity)

So as i'm sure we all know there will always be a compromise somewhere i just felt the need to highlight some, of course depending on your budget you can experiment and if you decide to do so i would recommend that you perform user A/B test with on the current and the new solution.

Again, my final advice would be not to change the order unless you really must