What app combines photos into one?

Many times you want to post multiple pictures on social media or text to friends, yet would prefer just combining several photos into one photo. Also with todays photos being so large, it would be nice to combine them but also have the size smaller since you dont need massive images when texting or posting online. The app "Combine Photos" is shown in the screenshot below and it does exactly this. You combine photos into one final photo, whether its 2, 3, 4, 6 or even 9 photos you wish to combine. It also lowers the final max size to no larger then 2048, which makes it much easier to post online and much easier to text to others, and yet the quality remains excellent. Your original images also still remain untouched in your photo album.