This app was mentioned in 6 comments, with an average of 1.50 upvotes
Maybe see if Gif Me! - GIF maker will work for you. The free version has ads. The pro version is pretty inexpensive at $1.49
quick search showed me this. I'm pretty confident that this app works on your phone.
Also imgur has a video2gif mode so you won't really need that :)
I use Gif Me!: https://play.google.com/store/apps/details?id=com.xnview.XnGif&hl=en
Works well, also https://play.google.com/store/apps/details?id=com.spritefish.fastburstcameralite&hl=en fast burst camera takes like, 30 pictures a second you can then make into a gif, and also drop down, once taken, to 2 or 3 frames a second or somewhere in between.
Also works well.
Wat about "Gif Me!"