What’s the best way to resize app icons for your mobile app?

Irish App Developer Resizing Mobile App Icons

If can often be hard keeping up with Apples latest devices and the ever increasing number of different sized app icons which are required for app developers to keep track of.

If you release a universal app which runs on all iPhones, iPads and Apple Watches you’re looking at alarge number (28 at the current count!) of individual app icon files which your app is expected to support.

Leave any of them out and you not only face an annoying yellow warning in Xcode but also the potential wrath of Apple when they reject your app for not having all of the necessary graphic assets. And we know that all good app developers always like to remove the warnings from Xcode right?

So as an app developer (in Ireland or elsewhere) what is the most efficient way to convert your original app icon file from 1024×1024 into the myriad of other app icon sizes?

Maybe you load the large icon into Preview.. and spend an hour of your life downsizing every icon to the correct size, renaming it correctly, saving them and then dragging them all into Xcode?

Maybe you’re lucky and your app designer does all of the heavy lifting for you and just drops the icons into DropBox waiting to be included in the next build?

It’s maybe okay to do it manually one time if you have one or two mobile development projects a year, but when you’re releasing several app updates a month, many of which can include updates to the app icons for ASO (app store optimisation), it can get a bit tedious for an app developer or even your designer resizing everything all over again.

Well, after spending too many hours tweaking app icons, exporting, resizing, and saving for inclusion in Xcode we thought there must be a better way.

And now, for us at least, there is.

It’s a new Mac OSX app we developed called ‘Alchemy’.

App Icon Resizer

Alchemy (App Icon Resizer & Image Asset Creator)

It accepts an original 1024×1024 icon and lets you export the full range of required icons for all iPhone, iPads, Apple Watch and Mac OSX apps.

Drag ‘n drop, make your device choices, and hit export and your done.

All icons sitting in a nice folder just ready for dragging into Xcode.

The added bonus is that it also handles retina image rescaling so if you have a large @3x icon or button you need downsized for older devices simply drag ‘n drop, hit export and you’ll end up with @1x, @2x, and @3x versions ready for including in your app.

We hope others can find this as useful as we have and judging by the reaction so far they have.

About Andy Dunn

Owner and lead iOS developer at Infinite Touch, Andy Dunn has been a freelance web and iOS developer for over 20+ years. Working with brands like Vodafone, Three, McDonalds and Tesco he lives and works from rural County Leitrim, providing app development services to companies all over the world.