This app was mentioned in 4 comments, with an average of 1.00 upvote
https://play.google.com/store/apps/details?id=com.inglesdivino.blurimage&hl=en&gl=US
Blur Image - it's a freebie :-) It allows you to pixelize or blur as you want, and you can adjust the level of blur or pixilation as you need.
I searched 'blur image' and downloaded the first app, which is this one. Doesn't look too fancy, but it works fine for what I need
for quick censors on mobile of pics I use "Blur Image" https://play.google.com/store/apps/details?id=com.inglesdivino.blurimage
it's got the best features from the ones I've tried