Three tips to create a great splash screen for your mobile app:-
1 - Use the right size
From one smartphone to another, the screen resolution can vary a lot.
Let's imagine you have crafted the perfect splash screen for an iPhone 5S. This image should mesure 640 x 1136px. It will look great on the iPhone 5S, 5C and 5, which have the same screen resolution. But what about the iPhone 4 which has a 640 x 960 px screen resolution? Displayed on the iPhone 4S or 4, your splash screen will be distorted.
To make the perfect one, you should create as much splash screens as there are screen resolutions. If your are creating an iPhone app, it's not a big deal since there are few devices.
2 - Keep it simple
The splash screen doesn't last very long. So no need to put a long text on your splash screen. Your users won't have the time to read it. And moreover, that's not the purpose of the splash screen.
Use your brand name, your logo, your motto, or whatever describes you and your app the best. Make a clear composition using those elements, and create one single image, in portrait mode.
If you want to create several sizes for your splash screen, I recommend you focus on the center of the image to put your composition. Leaving the edges of the splash screen free will enable you to crop your image to the different desired sizes.
3 - Tell your users it's loading
The splash screen is a still image. When you see it, it looks like your phone is frozen. Nothing happens. You can't interact with the app. You're stuck. You can only wait for the app to finish loading.
A lot of things can happen in the background when your app is being launched. Your app may need to upload or download data before being ready to be used. Your app launches some processes to boot correctly a new session or restore an old one ... Well, depending on the user's phone processor and/or the bandwidth the phone has access to, the time to boot your app can vary a lot.
To reassure your users, you should mention in your splash screen that your app is loading, and that within a few seconds of patience, your user will be able to use and enjoy your app.
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