You have to check out a speedreading app called Fastr. After I got over the learning curve (which takes about 10 minutes of use or so), it has effectively doubled my reading speed.
Fastr operates on the same principle as comparable reading apps like Spritz and Squirt - by flashing words in front of your face at a controlled rate, the app minimizes your eye movements to save you time and energy in making you an unstoppable reading machine.
Here's Spritz, for example. It's still in development and has yet to be widely available on desktop or elsewhere:
Spritz
Here's Squirt. It's desktop-only for now:
Squirt.io
But Fastr brings this same functionality to your iPhone or iPad, and it's awesome. Here's what it looks like to read at 420 words per minute:
YouTube
The average person who reads silently is doing so at approximately 200-220 words per minute. Fastr will let you tear through books and novels at up to an eye-popping 1,600 words per minute, but it's a pretty unenjoyable experience at that speed. Over time, you'll establish something of a default speed that words for you.
After some experimentation, I've identified my sweet spot as being between 400-450 words per minute. I also found reading one word at a time to be disorienting, but Fastr thankfully accepts options to include more words per line, or to even add more lines of text to each screen. I'm set up to read one line of two to three words per screen. This makes things fast enough for me to finish a couple chapters on a lunch break and slow enough to still enjoy what I'm reading.
The only downside to this app is that it's incompatible with your purchased Amazon Kindle books. They contain DRM to prevent them from being used anywhere else except a Kindle device or Kindle app. If you want to make this your main reading app, you'll have to read ebook files without DRM in them, or figure out how to remove it. Fastr includes an integrated "bookstore" of DRM-free ebooks in the public domain, so there's plenty of free reading material to get you started.