You can use voice dictation and feedback to navigate a phone or tablet if you're blind, but that doesn't really answer all your needs. What if you need to read charts or other graphics? The University of Michigan has an answer. It's developing a Braille display that uses microfluidic bubbles (filled with air or liquid) to produce the format's signature bumps on demand. Unlike existing Braille displays that rely on motors, this doesn't use up much space -- the school envisions mobile tablets that pop up dots whenever (and importantly, wherever) you need them.
Importantly, the technology relatively cheap. While a full, multi-line Braille display would cost $55,000 using established tech, the microfluidics should keep the cost of a tablet down to under $1,000. That's inexpensive enough that many blind people could justify getting one for reading, communication and even some basic graphical elements. Although this wouldn't be a full substitute for visuals or touchscreen input, it would deliver some of the spatial information that sighted people take for granted.