Do you spend most of your workday in front of a computer screen? If so, you may find that your eyes hurt or that you have trouble sleeping. This is because screens typically emit blue light, which the Harvard Health Publishing article "Blue Light Has a Dark Side" advises can be helpful during the daytime but harmful at night.

One tool that's useful for protecting your eyes is Iris, which you can download at iristech.co. Iris is a software that makes computers easier on the eyes by actively adjusting the blue light that screens emit. It comes with nine pre-programmed settings, and you can also create your own settings to ensure that the light from your computer screen suits your eyes' needs.

Iris offers a seven-day free trial, which you can extend by referring the app to friends and colleagues. After the trial ends, you have options to purchase Iris, including a $15 one-time purchase fee, which excludes future updates, or a $2-per-month subscription.