A free program for Android, by UTDevelopers.

Photo Blender Editor / Photo Mixer is an awesome and fun photo editor app, that will let you combine multiple pictures into one using various editing tools. With it, you can add different elements to your photos, such as text, stickers, filters, overlays, etc. In order to achieve the desired result, you will need to use different editing tools, such as the ones available in the app, as well as others, such as the ones you will find in the app’s settings. 

The app will also provide you with various options to let you create the desired photo, such as the color of the elements, the opacity of the elements, etc. It is very easy to use, as it has a simple user interface and a detailed tutorial, that will help you to use the app.