Some ideas of how to work with images:
Due to the a lack of a standard in the making of the devices, the ratio between height and width varies. That means we can't give a set answer for the image sizes.
When you insert an image, Mobincube allows you choose the % of width of the screen to use. The height will be set depending on what we chose as a width but always keeping the original image proportions.
If we use a small image (low number of pixels in width and low resolution) and we set it to fill the 100% of the screen width, the image will be shown distorted, with big pixels. A good rule is to use a resolution between 150 and 250 dpi (resolution) and between 1024 and 2048 pixels of width for a full screen image (100% of screen)
In the same way, if we want a menu in a bar (a table with 4 cells) when the icon takes 25% of the space in a cell, the image should be at least 512x512 pixels.
The main app icon in the info tab should be 512x512 pixels too.
If we need an image to fill all the screen, the best way is to fragment it, for example, is if we have an image of 3000px x 1500 pixels, in a device with that screen resolution will fit perfectly, but on other devices the image will be either longer or shorter and will leave a blank bar in the bottom.
Instead, if we use the 'background colour' to define a plain colour, this will always fit the 100% of the screen. If we set smaller images on top of it with same colour as the background colour or a transparent image...:
:...the images composition and the background colour will be shown as we desired.
If we press command and control in osX, or right click in any image in a template, we can save the image to our computer and use it for any other screen after we upload it to the image manager.
If you need a program to edit and manipulate images, and learn to make transparent images, you can try:
Working with images