I posted this on my personal blog elsewhere, but thought you guys might get a kick out of it, too. It IS about reading and writing!
Spritz is a mobile application for fast reading, which flashes a text by you word by word at a given rate. Readsy is a web version which works with uploaded PDF and TXT files or a URL. I've been using Readsy to sprint through my reading assignments whenever I can.
There is a learning curve. At first, I didn't get the entire content of the text as it whizzed by. My attention wandered and I started to get sleepy. I noticed it helps if I do something with my hands at the same time, such as braid and rebraid my hair. But the key is just heightened attention. You have to pay proper attention to the words.
Even when paying attention, you will not be able to read words you're not familiar with. The process depends on you recognizing a word's shape rather than each individual letter. I noticed this while sprinting through a text on paleolimnological research into arctic lakes: Constant reference was made to a particular microscopic water creature that started with C. (I didn't go back to check...)
Some PDFs don't work as well as others. It of course has to be machine-readable, but additional coding attached to it, such as DRM, will also make it unreadable for Readsy. I've had success in copy-pasting a text and printing to PDF on Word. The one time I tried to upload a TXT, it didn't work.
Another constant source of annoyance with Readsy, when using it to read scientific articles, is that you can't make it skip attributions or image texts, or even page numbers. If you want an uninterrupted reading experience, you'll have to clean the text up first.
Of course reading the text in its original form is better. But Readsy is faster, and my reading list is sometimes enormous. So I do find it useful.
Hemingway is a web and a desktop app for streamlining your writing. It highlights adverbs, over-complicated sentences, passive voice and superfluous words. I went for the desktop app and run it on Windows 8.1. I would say use the online version instead. On my desktop app, highlighted words or sentences sometimes hover over the base text in a way that makes it difficult to edit that text. And with the beta online version, you can do everything you'd do with the desktop app, so it's really only if you often use your PC offline.
I don't take its instructions as dogma when writing fiction and obviously not for poetry, but for anything like an essay it can be very useful. Maybe not so much for me, since most of my essays are in Finnish, not English. And it can certainly help improve fiction as well, though you have to be your own final judge on whether to go for clarity over the beauty of the language for a particular scene. There's a reason this app is called "Hemingway".