[Tarana]

If your Kindle is getting slower, there are three likely possibilities. Your Kindle is having problems getting a file to index so is endlessly indexing. Your Kindle has very little space left (books with illustrations take up a lot of space). Your Kindle needs a factory reset.

Nearly always, it's the factory reset that fixes everything. It's just a pain though if you like to keep a large library because now you have to reload it and reshuffle into assorted collections.

I don't have anything to recommend other than avoiding tablets if you can. Tablets are heavy and harder on the eyes, although they are better suited for pdf files such as magazines. For currently selling ereaders, I only have experience with PPW and Nook Glo and both are good choices, but use different formats.