What do you use for editing and posting picture?

I am wondering what everyone uses to do their side by side comparison pictures? I would like to do one with my morning of surgery, one month and two months out pictures. I would like to do the 3 front facing ones on the top and the 3 side view pictures on the bottom. What have you used to do this? I see some great ones with the date it was taken and the weight written on them. I would really like to do this. I always found the pictures that show a time line so inspirational. Thank you for any help and ideas. 

I use an app on my phone called Muzy.

Thank you. I will look into it.

you can also google online photoshop.  There is a website you can use to edit photos like that.

you can also google online photoshop.  There is a website you can use to edit photos like that.

just realized I was logged in under an old username. :o)

I use an app called pic stitch.