This RSS Reader has only a size of 190KB and contains all important features of a rss reader. Unlimited feeds. Without ads. For free! It supports nearly all feeds and notify you when a new articel is out! It uses the material design from Google.
This App based on the Open Source Project Sparse RSS. Here is the source of Sparse RSS: https://github.com/doits/Sparse-RSS and here is the license: https://github.com/doits/Sparse-RSS/blob/master/LICENSE