EyeQue has a smartphone vision test you can do at home, and the company has a Kickstarter to fund the second-gen product called VisionCheck 2.
Some claim to have online or app-based refraction tests, but they are merely prescription verification services based on visual acuity estimates. EyeQue users are actually performing a self-refraction test while proprietary algorithms process, personalize, and store results.
Check It Out: EyeQue Unveils its VisionCheck 2 Smartphone Vision Test