Regarding not having any experience of blindness in your life, allow me to respectfully recommend the following, especially if you’re into game development and want visually impaired players of said game: GO to your nearest Boots Chemist and drop a pound or two on a set of sleep shades. Then, after you finish a development stage or project and want to find out what the user experience is for those without usable sight, strap those bad boys on and take your app for a spin. In other words, immerse yourself in our world, even if only for minutes at a time. We have a favorite sales and demonstration person who works for a certain company here in the states that writes adaptive software for Windows computers, and he decided the only way to learn the product he was hired to sell was to learn how his customers use it. He does all his sales presentations to large audiences in just this way, turning the monitor away from him so he can’t see it, and turning up the volume on the speaker so the audience can hear what he’s hearing and know what the user experience for a visually impaired person will be.
Hope this helps.