There's a new category in the Objects/Patches menu of Patches: Hotspots. These will make it very easy for you to add pop-up cards that open up on interaction.
To create the basic pop-up card hotspot, just drag and drop the "Hotspot" item from the Objects menu to use it.
To change the contents of the hotspot, you have to into the visual programming side of Patches. Press Tab to show the patches. Then press the Edit icon of the "Hotspot" patch to see its content. From there you can see the three images that make up the hotspot - Open icon, the info card and Close icon. These are all just .png images. Press their edit button to upload your own.
You can move the hotspot to your desired location by using the Move and Rotate tools that you can find in the top toolbar of Patches.
Here's what the final result will look like in action.
There's also another hotspot called "Video hotspot". That one is quite self explanatory: instead of popping up an image, it will pop-up a video. Just like the image one, you can upload your own video. You may have to publish your project to see the video play correctly.
Happy hotspotting!