What a coincidence, we just put something together in the last few days! Ours is a website, hope you can check out Keepinsta. It downloads both photos and videos.
Haha, awesome. I had a bookmarklet that contained just 1 single line of code that catch images of Instagram. But it was much generic and don't work well. So, I start study JS ES6 and I decided reformulate.
Keepinsta is cool! Congratulations.
There are some terrible websites with Spyware and more ads than yahoo.com! Keep at it, Theus :)