Smartphone apps have the potential to measure standard metrics of visual function. In addition, new tests may serve as digital biomarkers to detect early progression of disease, assess risk of developing disease or expand the patient's clinical picture. Smartphones are inherently advantageous to reduce the reliance on specialist bulky and costly equipment that currently only exists in specialist clinics. While there are some smartphone apps available for vision monitoring, very few have any clinical evidence to support reliability, validity and diagnostic accuracy.

The OKKO Health app (www.okkohealth.com) is a smartphone app available on Apple iOS and Android platforms, consisting of short games with applied vision science technology to measure visual function in an engaging way. The app has one game per function, each on average 1-2 minutes. There are 4 game modes available testing visual acuity, contrast sensitivity, colour sensitivity and hyperacuity. This study will aim to validate these measures of visual function against gold standard clinical tests.

Inclusion Criteria:

• Participants with AMD in at least one eye
• Willing to travel to the clinic in Exmouth/Bristol
• Able to hold and use a smartphone

Exclusion Criteria:

• Significant ocular pathology other than AMD
• Unable to provide written informed consent

People with dry or wet age-related macular degeneration.