For aging eyes, a magnifying glass is an incredibly useful tool. Unfortunately, a magnifying glass isn't always readily available.
Fortunately, your phone is usually within arm's reach. You can turn it into a magnifying glass with the right app. I recommend the Over 40 Magnifier and Flashlight for Apple gadgets and Magnificent Magnifier HD for Android users.
These magnifying apps use your smartphone's camera to enlarge what's in front of you. They also take advantage of your phone's flash, which can help if you're trying to read in a poorly lit area.
Cost: Over 40 Magnifier and Flashlight is $2; Ultra Magnifier is Free